Chinese sources are indicating that AMD has been working on a new high-performance core for two years now led by Jim Keller the engineer behind the original Athlon XP & Athlon 64.
This new architecture is supposedly going back to AMD's traditional multi-core approach with no modularity or resource sharing.
The new core is set to follow Excavator which will be released in 2015

Sources : [ Register or Signin to view external links. ] [ Register or Signin to view external links. ]

The Chinese sources unanimously referenced "wall street" as their source, conveniently an interview with AMD's CEO Rory Read has just been published on WSJ.

Quote
WSJ: Lets talk a little about server, where your share of the market
Read: Has gotten much smaller.
WSJ: Has gotten really small. Are you giving up on x86 server chips?
Read: No. So lets be perfectly clear on that. I think that Bulldozer (AMDs recent processor design) wasn't the game-changer that people had thought it would be.
We went out and got world-class designers and world-class leaders like Jim Keller or Raja Koduri that came over from Apple.
Theyre working on next generation work in that space, in the server space, in the cores space. And thats going to be both ARM- and x86-based.
Interestingly enough AMD's (and Intel's) high performance cores are always designed for servers. Both Bulldozer & Piledriver were engineered specifically with servers in mind. So it seems AMD's CEO has inadvertently reaffirmed the rumors floating around.

This has been [ Register or Signin to view external links. ] and is no longer a rumor. AMD is working on a new "from scratch" x86 high performance core along with a "sister" ARM core dubbed K12.

I thought that AMD was focusing more on the mobile side of things, but it seems like they are going the extra mile and bringing out some really cool tech. Will definitely be worth keeping an eye on these, heck I may even invest in one.