They did an excellent job of making you feel like a super acrobat, leaping and climbing insane places. Has a great feel to it, capturing the essence of the original without the frustration it had. The levels are creatively designed, and the combat is intuitive but fun.
So the two biggest complaints I've seen are too easy, and too short. Both of those are legitimate points, but I would argue that with the rewind time feature, what they have done was cut out all the boring parts. Instead of dying because you made a stupid mistake and jumped left when it should have been right, and having to spend 10 minutes working back to that point from the last save spot, you go back 5 seconds and don't do it again. This eliminates the repetitive and boring parts of playing a game, and leaves 100% enjoyable play time.