I'm buying it. I agree it's probably not everyone's cup of tea, but it has several things that interest me:
1. Gameplay wise, it's essentially a 2D platformer, one of my favorite genres.
2. It oozes style. The sack-boys are great characters.
3. It has an awesome level editor. I like playing around with level editors and creating my own game levels/objects.
4. It has a rather cool online setup. Youtube-like level rankings, etc.
Granted, I'm also interested in Blast Works and Spore... I guess I just have a thing for games that allow the player to do a lot of customization using fancy, built-in tools.