Anyways, here is the LINK so go check it out completly.
Some early benchmarking done in a Desktop PC:
Hitman: Absolution (1920X1080)-Low
HD 8790M: 39.7 FPS (no AA) 25.1 FPS (2xAA)
HD 7670M: 27.2 FPS (no AA) 18.5 FPS (2xAA)
HD 8790M: 18.6 (no AA) 13.9 (2xAA)
HD 7670M: 10 FPS (no AA) 8 FPS (2xAA)
We can see it is a major improvment from last-gen but still can't be used for good, quality gaming.
The release date is somewhere in Q1-Q2 (maybe).