[Disclaimer: The following review is based on my opinion of the game and should not be interpreted as a technical dissection of the game and it's underlying systems.]

I really want to like this game, I really do. I'm a huge fan of 40k and Final Liberation.

The biggest problem is all of the games tactical potential is completely obliterated by the missions railroading you into stupid objectives to complete in an entirely arbitrary number of turns. This is not a game where you get to devise your own strategies and carry them out. Most of the mission objectives are "go from one end of the map to the other end of the map in 14 turns" or some variation there of; want to try out a gun line? Too bad. Want to try an infantry heavy force and engage in some building-to-building combat? Too bad. Want to soften up the enemy first with artillery and then use your cavalry to route them? Too bad. All you get to do is move your units to the highlighted hexes, and if you don't do it in 14 turns, you get the privilege of doing it over until you do it just the way the game wants you to.

Here's another issue: the unit cap. You're limited to an arbitrary number of units, and none of the units have any sort of variation in the number of squads that you get for the slot they take up. Essentially there's very little balance between the unit variety, with some being just flat out better than the others, and point cost is rarely an issue past the first few missions; long story short, why would you ever, ever, EVER take infantry in the late game? Rheotorical question; you wouldn't, because the game sucks.

Oh, the deployment zone sucks too. It's just a random sprinkling of hexes you CAN deploy in adjacent to a bunch of hexes you CAN'T deploy in with absolutely no logic differentiating between the two.

If the guys at Slitherine aren't too busy developing spread sheets for the D-bags on Deadliest Warrior to plug fake stats into so they can test who would win in a no-holds-barred brawl between an Apache Warrior and an Apache Gunship for science, here is a short list of things you can do to fix your crappy game:

1.) F*ck the turn limit
2.) F*ck the unit cap
3.) F*ck the deployment zone and FIRE whoever came up with it
4.) Have an actual campaign map, and give the player some actual agency over what they're doing (this is optional, since it would require actual game development and I'm sure you've got spreadsheets to make or something)

Very overpriced, with missing features and terrible A.I. Just as overpriced as the models.

Warhammer 40,000: Armageddon is a hex-based strategy game set in the distant future of the 41st millenium, where the orks have once again invaded Armageddon.

Before we get started with the review itself, let's get a few things out of the way. This game is not an attempt at making a direct adaptation of the popular tabletop game by Games Workshop, though it is set in the same universe, nor is it an attempt at making a spiritual successor to Final Liberation (an old PC game), which some reviewers seem to indicate was what they expected it to be. This is Panzer Corps with a 40k coat of paint (Panzer Corps in turn is like a modern update on Panzer General 2, which had its own 40k version called Rites of War).

Graphics & Sound
At first glance 40k: Armageddon is not an impressive looking game. While the sprites are relatively detailed, and the maps look good, the sprites look like they hover above the map. The game does not fare better in motion, with very simple looking animations for firing, and no animations for movement.
The sound is equally underwhelming. It does its job, but nothing about it really stands out. The weapons sound like what they are supposed to be, for the most part, but for a game world known for having oversized guns, almost to the point of self parody, one would expect there to be a bit more to the sound effects of those guns.
But while nothing looks & sounds particularly impressive, everything looks like what it's supposed to be. Anyone with a basic knowledge of the 40k universe will be able to identify most vehicles and units and figure out what they are armed with by just looking at them. And this ease of identification is very important to the game, as there are a lot of different units to keep track of.

Story
The story in the game is not given center stage, instead it just serves as a reason for why you're fighting on Armageddon. It follows the second war for Armageddon, one of the most important wars in 40k history. If you're familiar with 40k lore, you'll likely know exactly what's going to happen, so the story will offer no surprises. To anyone not familiar with 40k lore, the story will likely feel poorly explained. This is not something that really hurts the game though.

Gameplay
It's in the gameplay department that 40k: Armageddon really shines. Before each battle, you're allowed to put together an army consisting of imperial units (at first only Imperial Guards, but later you also get access to Space Marines). And there's a staggering amount of units. The game boasts over 300 different units in total, between the two sides. With so many units, you're given a lot of freedom to design a force that suits your playstyle, and the upcoming scenario. And the vast majority of all units feel useful. Someone could probably figure out which units are the optimal ones, but there don't seem to be an glaring balance issues (take note GW).

The battles are played with a simple IGOUGO system, meaning that you take your turn to move all units, and then the opponent takes its turns to move all units. Different units have different strengths and weaknesses, and are armed with different weapons, so like in most other games of this type, the trick is to use the right units against the right targets. Infantry in good defensive positions are hard to dislodge without melee units, tanks need anti-tank weapons for you to effectively deal with them, and so on. Certain units are able to support other units when they're being attacked, and making good use of terrain & choke points is often important. Nothing about the gameplay is groundbreaking, but it is well made, the scenarios feel challenging but fair and the game is a joy to play.
Every mission has a turn limit. This is something that a lot of people seem to dislike, but without the turn limit, the game would probably have become too easy. Personally I've always had several turns to go after each level, and the turn limit has never interfered with my playstyle, but anyone who turtles a lot might run out of turns.

Closing thoughts
Warhammer 40,000: Armageddon is a really good game, and it's a really good 40k game. It does the license justice and is often more consistent with how it presents things than the official writers for GW, who often contradict core portions of the lore.
The only reservation I have is about the price. Niche games are often more expensive, as they expect to sell fewer copies, but the price point of 40k: Armageddon makes it a hard sell to anyone who don't already know that they will like the game, and the screenshots make the production value look rather low. A lower price point would probably attract more customers who would be willing to take a risk at the game. Because it is a good game, a very good game, and it is a game with a lot of content. Don't be surprised if beating the main campaign takes over 20h. Fans of Warhammer 40,000, and fans of games like Panzer General should give this game a try. As for everyone else, it might be worth waiting for a sale, or trying the demo for Panzer Corps to see if they like these types of games (Panzer Corps is a slightly more complex game than this, but it's still similar).

Warhammer 40,000: Armageddon is a terrific game...for the right kind of gamer. Those expecting the second coming of Dawn of War (technically, third, I suppose) will be sorely disappointed. Those looking for a solid, turn-based strategy (TBS) game on a hex-based map will likely be quite pleased. Fans of the WH40K fluff will also be pleased, as you get to personally participate in the major events that make up the 2nd War for Armageddon. Personally, I'm loving the game thus far.

In terms of raw gameplay, the game itself is very much an old-school wargame. It's somewhat similar to games like Steel Panthers, although it's perhaps not quite as granular in its depiction of combat as that series. I haven't played the Panzer General or Panzer Corps games, but I hear it's similar to those (Panzer Corps especially, which is no surprise since they're made by the same company). Anyway, it's a TBS game on a hex-map. Units are allowed one movement and one firing action per turn (although you can move more than one space, obviously, and units with multiple weapons will use all of them, if they're in range). Alternatively, you can reinforce a unit, or recover morale.

At this point, I've only played Act I, but there is a good variety of units available. It can actually be a bit overwhelming at times, and you may find yourself turning towards both the game's manual and the online message boards for information on the difference between a Leman Russ Vanquisher and a Leman Russ Conqueror. Once you learn what the different units do, though, you realize that you can build a very specialized force (or a very general-purpose force, if you want). On the surface, the game may seem fairly simple to veteran wargamers, but there's depth to be found as well, in terms of different terrain effects (Line of sight, cover), units that support each other (meaning that, when the supported unit is attacked, the supporting unit will retaliate as well as the attacked unit), and all the usual rock-paper-scissors (or infantry-artillery-cavalry, I guess) balancing you'd expect in a wargame. I found that, while initially bewildering, once I understood my options better, I really appreciated the variety, even as it sometimes made it difficult to decide what units to bring in a given scenario.

Your core force will gain experience as you play, and you can change experienced soldiers into different unit types within the same class (so a bog-standard infantry unit can be upgraded to a harder hitting unit) over time. You'll want to do this, as the difficulty ramps up and you find yourself facing tougher challenges that require a more specialized response. Understanding what the different stats mean will help with this. I recommend looking at this thread from Slitherine's (the developer) board: http://www.matrixgames.com/forums/tm.asp?m=3827148.

Story-wise, for fluff fans...it's the 2nd War for Armageddon, with you playing as the Imperial Guard. You can probably guess what you do in it. For those unfamiliar with the WH40K fluff, the story is fairly typical of the in-game universe. You have a planetary invasion by an enemy force (Orks in this case -- no chaos or eldar so far, but we can hope for DLC...). You play the primary campaign as the Imperial Guard -- the "grunt troops" of humanity, rather than the elite Space Marines, at least at first. (After the first Act, you can start playing as the Space Marines, and get access to Titans as well.) You have a LOT of vehicles to bring with you (which is your major strength), so you can really enjoy some combined arms action. Anyway, aliens invade, incompetent planetary governor puts everyone in peril, and it's up to the Guard to save the day or at least hold out long enough to be reinforced/relieved. Missions are a nice mix of assault, defense, and maneuver, and sometimes a bit of all three in the same mission.

I'd say the only other major caveat (aside from this being a TBS game and requiring you to actually learn how to play it) is the graphics. Look, this isn't a AAA whiz-bang graphical cornucopia. The game isn't designed that way. Your units don't animate, really (although you have the animation of different types of weapons firing and such). This isn't Total War, where every individual trooper is animated and doing his own thing. That said, the sprites in the game are perfectly fine for what they are, and look sufficiently detailed. I have no complaints about the graphics, but I knew what I was getting in the game and had no illusions about the graphics. The hand-drawn panels and backgrounds that serve as the "cutscenes" between missions, however, look lovely. Again, though, they are static and not animated. Voice acting is perfectly fine for the game. It's not Oscar-worthy, but it gets the job done perfectly well.

On the whole, I really enjoy the game, but I'm also a fan of the fluff and of games of this sort. For my money, it was definitely worth the price I paid.

If you love Warhammer 40,000 you might like this game.

This game has a lot of missions, a lot of units, and a map editor.

There ARE some glaring issues with this game, most notably the lack of movement animations for any units. The missions are also repetitive and the use of "victory hexes" gets old after the first act. There are also only three factions: Imperium, Space Marine, and Ork. The game IS about the Second War for Armagedon (a major conflict in the lore), but I hope they make a sequel that adds the rest of the factions on a less centered story.

I am recommending this game only for hardcore fans of WH40K, if you aren't then skip it until the price goes WAY down.