From what we´ve seen, the R700 is a small single core and if you want a high end you will have to put more of these together.
With lower dissipation and 45 nanometer it will be possible to have four, or even six, smaller cores. The R700 single core will be similar to what we seen in the guise of the RV670, but it is still too early to have too many details.
The new chip will support DirectX 10.1 and Shader model 4.1, among other things. Imagine a chip that can have three or even more times performance of RV670, and this might give you a glimpse of what is coming.