360 version - my thoughts.
Yes, I did get a few freezes (and since apparently there's a limited amount of space available for saving games, I got sent back to the beginning of the mission - not extremely frustrating in the slightest). Sometimes they were straight up freezes, but most of them were "graphics-overload," as in there were too many enemies on-screen to draw at the same time and the game spat out a "disc not clean error." Oddly enough, turning it right back on and playing it seemed to clean the disk. Thanks Microsoft.
As far as gameplay goes, it definitely kept me entertained. There are a few annoying things (the camera can be a massive PITA during fights), and sometimes the fight system doesn't work the way it's supposed to (but not often). Overall, the collecting aspect of the game wasn't too bad, and there's nothing quite like a stealth assassination - whether you're supposed to or not. It has a few other nitpicky flaws, but it was a fun game overall. Well-spent $60, considering how much playtime there was (No, I'm not exactly certain with the freezes and the fact that it's Thanksgiving Break and I haven't slept in two days).
Story-wise, while the twist was fairly lame (not going to spoil it), it did seem like they used as a crutch for level design. Instead of the wide-open sandbox I expected, there were arbitrary barriers set the various cities for no discernible reason whatsoever. Of course, the twist comes in very handy for skipping what would otherwise be exceptionally long travel sequences (I'm looking at you, Shadows of the Colossus). The only solid reason for the twist is it allows the sequels to have a different time sequence than this game, which should prove somewhat interesting.
Genre-defining? Hardly. But if you liked Prince of Persia, chances are you'll like this game. If not, see if I give a damn. I thought it was fun.