Apparently I'm not saying anything new about this, since it's so highly rated and regarded already, it seems, but nonethless:
A game that I have played, stopped playing, and come back to playing again many times over the years. I've enjoyed it a lot, and for some reason a big title or two will come out and I'll eventually forget about galactic civ. for a while, and then eventually I'll stumble upon it... always surprised by how much I enjoy playing it, time and again.
It lacks some of the graphical 'bells and whistles' of a Civ-type of turn-based strategy game, but as any player of ck2 knows, what a game lacks in polish can be very much made up for in actual game content and replayability. The depth of galactic civ (and ck2, for that matter) makes civilization look like simplistic child's play (unplayable to me, as a by-product) in comparison.
Distinctive differences/cool elements of the game:
- Skill trees are actually unique to every race.
- fully customizable ships (designing ships became one of my favorite elements of the game early, to my surprise).
- plot/narrative elements that differ game-to-game, making it very replayable.
- Races themselves are fully customizable, adding another layer of replayability and depth to the game's customization.
On the downside, it has many layers of things to control and 'develop,' so to someone coming to this from civ or simpler games of that nature, galactic civ could be daunting, by all means, even overly so. This is a game for a real turn-based strategy-lover, who wants to have a depth of 'control' that might be beyond the average gamer, whoever or whatever that even means...?
I'd say for a strategy-lover (someone who likes games like ck2, europa universalis, etc.) it's a must have regardless of price (I don't think it's more than $20, this far from publication). If you're a civilization/spore lover and you're worried this might go a little too deep and not have the 'sheen' you look for in a game, wait for it to go on sale, as it does every so often, and get it for $5, and give it a shot; Who knows? The developers clearly labored over it with love, and put in a lot of good work in making a very fine game (as I see it).