The first details of the ATI R700 indicate this upcoming high-end card will feature four or even six cores. The chip is expected in mid-2008 and will support DX10.1 and SM4.1.
FUD Zilla says the GPU will feature four times the theoretical performance of the RV670 which gives it a chance to break the 2 teraflop mark.
The RV670XT is close to 500 gigaflops, while R700XT might even get as fast as 1.9 teraflops, if not even more. Depending on the final clock the new card might even do 2 Teraflops and this will certainly speed up games or GPGPU calculations, up to four times.
The site also claims the R700 will be released as part of the Radeon HD 4000 generation, but it's possible that the name will change.