Had a friend pick it up for me when he went to Baton Rouge yesterday, I'm on world. . . five or six, can't recall. The place after the snow area.
So far, absolutely awesome. The controls seemed to loose at first, but now I'm perfectly used to them and doing fine. The platforming is awesome, and I love the new elements. Next sentence is a minor spoiler: Especially like the castle where you just move up vertically on that platform while avoiding spike balls.
Ian, I also move while playing platformers. I noticed today, I was playing while my cat was sitting on my lap, and I kept bothering it because my leg bounced a little every time I jumped, trying to get a little higher

More impressions later, but halfway-ish through the game, I like it a lot.