It's pretty tight.
I'm on the third level. It uses Prince of Persia mechanics, such as running on walls, climbing them, and stuff like that. It even has little narration of the levels, just like when the Prince chimes in. The levels are straight forward, and it runs pretty smooth too. Graphics are pretty bad, and the fighting isn't really good, just mash the button and you win. But there's a lot of enemies, and they pop up at open areas, and you are forced to fight them in order to proceed.
I think it follows the movie, I'm not sure. I'd have to see the movie.
Also the achievements are piss easy, all I have to do is beat the game.