This one combined the improved combat of Warrior Within with a lighter mood more reminiscent of Sands of Time. Sounds good as a description, but somehow I like less it than either of them. It doesn't come anywhere close to the atmosphere of SoT, and it feels much more "safe," sanitised, and focus-group-approved than either game.
This was released around the time that quick time events were becoming a trend, so obviously they make an appearance. Simplistic stealth mechanics have been added, and you can kill enemies from behind by starting a long and drawn-out animation punctuated by pressing the attack button at the right moments. This gets very repetitive, particularly because there's only one animation for each enemy type, so you'll repeat each action dozens of times throughout the course of the game. Sections where you ride a chariot are a strange addition to the game too; enjoyable enough, and don't really feel out of place, but I have to ask myself "why did they focus on this?" Prince of Persia didn't need stealth, quicktime events, or chariot races. These things are just gimmicks, something to throw out before the next game is made, and don't really add anything of value.
The environment seems much more artificial, closed off and unnatural, making little attempt to hide the fact that it's designed specifically for the Prince to navigate through. Obviously gameplay should come first, but in the other games I feel there was more effort put into making the worlds have a logical consistency, so immersion suffers here. Platforming itself makes the least sense of any PoP game, as you'll bounce off weird springboard things that have no reason to be there, and find the same metal grid object on every wall for you to stick your dagger into. It feels like a playground set out for you, rather than a living world that you're making your way through.
As far as good changes go, the camera has been adjusted quite a lot, and it's much tighter and rarely causes problems anymore. Unfortunately widescreen support was an afterthought and the game isn't really designed around it, so the FOV is too close, the camera will snap back into position if you look up too far, and the composition in cutscenes is broken. I can't really fault the game too much for that though, it's from 2005, so just play in 4:3 if you can. Sections where you play as the Dark Prince are fun, and add some nice variety to the gameplay, but usually don't last nearly as long as they should. Farah is back in this one, but she's now a very generic icy action girl (with an American accent). Hm.
Continuing their proud tradition of making terrible PC ports, Ubisoft broke the anti-aliasing this time, so when it's enabled it causes lighting issues. You'll get some other lighting problems (flickering, or sudden changes of brightness) even with AA disabled, and there's nothing you can do about that. These issues have always been there, and aren't due the age of the game. It will occasionally crash during loading screens too.
The solid gameplay is there, for the most part, buried under gimmicks. But this one has very little else to charm you with. It feels shallow and disappointing.