Update!!
I just found this at:
http://www.rivastation.com/comdex-ati_e.htm
RS: What has happened to the RADEON MAXX? Weren't there originally plans for this card?
Martin Traute: Despite rumors to the contrary, the RADEON MAXX has not been cancelled. However, there will not be such a version using the current RADEON core. Instead, we plan on offering it with its successor (RADEON2). The reasons are technical, as we are having trouble with the bridge for the two cores. So far it only runs stable at AGP 2x. We want a card of this format and caliber to be available with full AGP 4x support, however. It's looking very promising, though and we are very confident."