As promised, the new Gorillaz album showed up online over Christmas, and it's available for download right now. The album is called The Fall, and you can listen to one of the 15 tracks, called "Phoner to Arizona," embedded after the break. The whole record was made completely with an iPad, and CNN has a list of apps used to make the album, including Amplitube, Mugician (written by a TUAW commenter), and Moog's Filtatron, among quite a few others.
I just gave "Phoner to Arizona" a listen, and it's ... weird. Weirder than I thought -- the Gorillaz are already pretty trippy, but this seems much more like an experiment than an actual album. Still, it's worth a listen, and it's an impressive feat to build a whole album using just Apple's iPad. Again, you can hear it for free on the Gorillaz' website, or join their fan club to download it yourself.