More than a refreshing twist on the platformer/puzzle genre, I would say it is a refreshing twist in videogames in general.
There is time reversion, time twisting, time dilation and even (my favourite) alternate realities. I think the concept is incredibly innovative both in terms of game design but also in terms of game engine design, as I do not see any easy way of keeping such a coherent interaction with time.
I absolutely loved the art - the drawings, the background, the music, the story.. impeccable. The story kept me reflecting on it for quite a long time, and I cannot be absolutely sure I understood the ending. I won't spoil it, it's really special.
Despite the fact that you can technically never die, the game can be very challenging both in terms of puzzles and in platforming skills. Luckily the time reversion mechanics saves (real-world) time when you miss a jump requiring an almost pixel-perfect execution, so the game is actually very forgiving and treats you with respect at all times.
The game has absolutely no filler and it is incredibly satisfying, but I can't help thinking a few mechanics, like the alternate realities one, could use a bit of further exploration. I got a bit annoyed with the "time dilation" levels as they were the ones which required the most platforming skill, but, hey, it's the game's last levels, they are supposed to be challenging in all aspects :)
A true masterpiece - check out the demo at braid-game.com, have a bit of patience as the first few levels are a bit slow and confusing (the first time I played the demo I was like 'meh' and deleted it, but yesterday I gave it another chance and got absolutely hooked).
I don't blog often (and even less often about games) but Braid is very special.
Also, those damn rabbits made me do it (I felt so happy when the insane rabbit family got fried by cannons for chasing me. Should teach them a few things).