I really liked this game. At first it looks like a very ordinary platformer (very good jump feel, by the way). but as the game advances and the level starts to react to my movement it's a completely different experience. I liked the powerups, the puzzles, the platforming, it's all tight. The way you tell the story partly with the scenery and part with the journal pieces is amazing.
Definitively my favorite part about this game is the interactive level, like the warps around the world, it has many respawn points and that lets me get back right into action, I love that. I love that when the level falls, it does kill you, but it's also opening new paths, so it keeps enlarging the level. I loved this game.