And now that Intel has decided to stop building its own motherboards (3 year phase out), I imagine AMD is wondering what to do. If x86 isn't 'dead' as marketing has proclaimed, then AMD could have the entire x86 market for itself; that's a pretty sweet peach, assuming it could handle the volume.
On the other hand, if x86 is dead (news to the tech community at large), hanging around (as opposed to, what, ARM?) is the better option.
And with Intel largely out of the market, the margins / profits on x86 processors would be pretty sweet. More than enough to continue fueling x86 development until we have an optical chip breakthrough (and even then, x86 is just the instruction set...so it could even transfer, much to the chagrin to many x86 Assembly coders).