The latest Nintendo Power (yes, Nintendo Power. Shut up.) has an interview regarding this game. I'll type it up if anyone wants.
de Blob was originally created as an art project (for PC) by a group of students in the Netherlands. In it, you roll around and add color to a black-and-white world. It's just a freeware demo, but someone at THQ was so impressed that they contacted the students about making a full game out of it.
Apparently, two completely separate games, one for Wii and one for DS, are being made out of it. I haven't seen anything about the DS version, but the Wii version looks awesome. (Apologies for linking to IGN)
Anyone else care? Although it will definitely draw comparisons to Katamari, it's pretty damn unique. This is exactly the type of game I've been wanting on Wii.