Looks like the albumsix.com site was a hoax conconcted by some Weezer fans, but accepted as a legitimate news source by Billboard, Rolling Stone and (gulp) us. The record has not been titled Tout Ensemble as previously reported, and Rivers adds:

Please note that Weezer and Geffen Records have no affiliation with www.albumsix.com. The new Weezer record is not called "Tout Ensemble" and there is no official release date yet for the album. Remember, when its on Weezer.com, its for sure. (Though I will say, "well played", to the authors of that site.)

The record remains set for a Spring 2008 release.