If the Devil designed a video game...
...it might look something like Super Meat Boy.
Everyone knows this is a tough game, believe the hype. It needs to be said that while it is tough, it is not cheap. You do not feel like the game is killing you in ways you could not avoid. Trial-and-error gameplay is at work here, and you have to be ready to learn from your mistakes.
This is a game two years in the making and it shows. Lots of "love" was poured into every aspect of it's design, though it never takes itself too seriously. The style is an accurate homage to past gaming eras.
The controls are tight and fluid on the Xbox 360. I've heard many say that they prefer to use the D-Pad to control Meat Boy, but I found the analog stick to have far greater response to the often calculating movement that is required.
This is a triumph of Independent Gaming, and the sales have backed up that fact. There is free DLC coming before the end of the year. If you were ever to buy only one XBLA game, this one should it.