It was on the Beyond 3D forums that a photograph emerged of what is most likely the Radeon HD 7970, based on a 28nm GPU.
The first Southern Islands 28nm GPUs will be launched in January, 2012 (next month) and should be given attention during CES (Consumer Electronics Show).
Moving back to the device in the photo, it has 12 memory chips, which implies a memory interface of 384 bits, something that AMD or ATI GPUs never showed before.
Also, the SIG approved 6-pin + 8-pin configuration of cables powers each of the two adapters, which implies that any one of those things can consume up to 300 W. Interestingly enough, the PCB has all it needs for two 8-pin connectors too (up to 375W of power).