Some ATI partners might do a GDDR4 version of Radeon 3870 X2. Currently, all cards on the market are GDDR3-based, but going to GDDR4 won't drastically improve performance.

Even a card with 2GB memory is possible, but again that wouldn’t really bring any significant performance increase, and at the same time it would increase the price.

There might be another 3870 X2 before R700 surfaces, but that’s another story altogether.