Although it was all but confirmed and certainly pretty much clear as soon as Microsoft revealed the official specifications of the Xbox One, AMD has also officially and quite proudly confirmed that it is AMD's silicon that ticks behind Microsoft's 8-core CPU Xbox One chip.
The Xbox One design win completes AMD's trinity of console wins that joins up with Nintendo's Wii U and the Playstation 4. Although AMD can't actually talk about any specifics regarding the chip and we'll have to stick with 8-core CPU part, 8GB of RAM and GPU capable of 768 operations per cycle announced by Microsoft, AMD can surely announce that it is a "semi-custom APU co-developed by AMD and Microsoft".
Both the Playstation 4 and the recently announced Xbox One share quite a lot of similarities and while Microsoft did not talk about Unified GDDR5 RAM and some early info suggest that Xbox One will feature 8GB of DDR3 memory, we will still have to wait a bit longer to see those performance differences between these two consoles.
In any case it is a complete win for AMD as no matter which console manage to win the console wars, AMD will share the spoils of war.