Being in the new Nintendo Wii U, PS4 and XBOX 720 may be a coup for AMD but I'm not sure I like it from a product differentiating standpoint.
This generation you have studios who are exclusive to each console manufacturer (Insomniac, SCEA Santa Monica, Naughty Dog [PS3]) / (Epic Games more or less, Bungie, Remedy, Lionhead [XBOX360]) who are developing on competing and different hardware to try and make the best AAA title.
If you take this away and have a similar Radeon GPU on both the PS4 and XBOX 720 you could get developers who just develop for the lowest common denominator between the two systems.
Worst case, you get games programmed for the Nintendo Wii U that look no better at all on the PS4 or XBOX 720, and we have a repeat of the Wii shovelware syndrome.
Of course, there will always be studios like iD and Kojima Productions who will massively optimize for each platform but these are too few and far between.
It will be interesting to see how this new generation pans out.