This game is pretty ridiculous. It's like the company asked a bunch of 4th graders to come up with ideas for a racing game, and this is the result. Wall rides, loops, huge jumps, crazy speed. It's awesome.
That being said, the skill cap is infinitely high. Yes, it's massively fun to go on a server and smash through a bunch of new tracks, crashing all over the place and hitting walls like they owe you money. And it's worth mentioning that since the multiplayer is almost exclusively user-created levels, there are tens of thousands of maps to play. But once you settle in to a server and have learned the maps, then it becomes a wonderfully technical game about shaving off bits of time where you can.
A notable game mechanic, for those unaware, is that in time attack mode (probably the most popular game type, that and Rounds) you can reset to the beginning of the track (or the last checkpoint) at any time. This is a bit of departure from many other racing games. You'll just have a set amount of time (usually 5 to 7 minutes), to get a single best run possible. This makes it so that you never have to waste time finishing a run when you've already messed up, you can just reset and start fresh immediately. Makes for a much more efficient practice regimen, and resulting rate of improvement.
There are three environments within TrackMania 2 (Stadium, Valley, Canyon), but within each environment is an abundance of variety in itself. Since this review is Stadium, I'll focus on that briefly:
-Track materials: Pavement, Dirt, Grass, Water
-Game Modes: Time Attack, Rounds. Probably others, but rarely used. RPG, I suppose.
-Track Types: FullSpeed (because braking is for losers), Tech (because fullspeed is for neanderthals), Dirt (because you are full of self-loathing), Speedtech (Because you're a well-balanced individual with many friends and a winning smile).
Seriously, the infinite permutations of tracks alone makes this game worth it.