TechPowerUp picked up new rumors that AMD's Radeon HD 7900 may feature Rambus' XDR2 memory. Additionally, the site also heard that AMD may decide to launch the high-end Radeon HD 7000 cards first, starting with the dual-GPU "New Zealand" model. Many of the low to mainstream models are expected to be rebrands though.
Apparently AMD and Rambus have had much more cordial relations with each other, than other companies the latter engaged in patent disputes with. In 2006, AMD settled outstanding disputes with Rambus by willing to pay licensing costs for certain technologies claimed by Rambus, turning a leaf in the relations between the two. What Chinese sources are suggesting now, is that AMD will design its high-end GPU (codename: "Tahiti") in a way that will let it support both GDDR5 and XDR2. Certain higher-end SKUs based on Tahiti will use XDR2, while the slightly more cost-effective SKUs will use GDDR5.
In related news, other sources told TechPowerUp that AMD could adopt a "top-to-bottom" strategy with the high-end portion of its next-generation of products. This means that AMD could launch the dual-GPU "New Zealand" graphics card first, followed by single-GPU SKUs.