Though ostensibly a platformer, Braid is really a puzzle game. A very clever and entertaining one.
If I had to compare it to any recent game, it would be Portal. It shares the same clever puzzle dynamics. It also shares the length -- it is not a long game. But that's good, because it means it's as long as it should be.
Where it's different even than portal is how the "gimmick" is different on every stage. Your control of time changes, and things you learned on previous stages aren't necessarily useful on later ones.
In conclusion: beautiful, mind-bending, and fun. Exactly the kind of stuff we'd hope for from indie developers.
