from it.oc.com.tw site managed to snag a picture of AMD's Matt Skynner holding up what appears to be the upcoming AMD's HD 6990 dual-GPU Antilles card. According to the info, it will be powered by two 40nm Cayman GPUs and although the specs haven't been officialy revealed the new cooler was detailed.
It looks like that AMD needed to completely redesign the cooler and the upcoming Antilles dual-GPU card will use a design that hasn't been seen on graphics cards, at least not yet. Apparently the card will use a cooler with a cylindrical blower that will draw air from the rear of the card and distribute it over a vapor-chamber heatsink, or to be precise heatsinks since we are talking about a dual-GPU card.
As it was expected, the card will need two 8-pin PCI-Express power connectors and should be released sometimes during this quarter. You can find the original post here