Super Meat Boy recently released on Xbox 360 Live Arcade and has seen great success so far. The game is an exceptionally hard platformer with very tight controls. You can play the original flash game over on Newgrounds right now if you want to see what it’s like. Super Meat Boy adds ton’s of levels and a bunch of unlockable extra characters from other indie games such as Braid, I Wanna Be The Guy, and Mighty Jill Off. The PC version is getting a few extra characters in the for of Veridian from VVVVVV. He retains the same ability he had in that game being able to flip gravity instead of jump. They are also adding Mr.Minecraft, the default character from the popular PC sandbox, to the game. No word on what his powers are but I would assume he can make platforms.
The links I have provided will take you straight to the games mentioned if you are at all interested.