$550/$600 7970 - Who'd of thunk it.
AMD isn't Nvidia, sorry.
I guess price gouging on both 7 series and bulldozer didn't pay off too well.
Initial $550 sticker shock of HD7970 aside, I think this really isn't about HD7900 series. We've known from info Grooverriding dug up a while back that only 3-4% of NV/AMD GPU stack comprises the overall discrete GPU sales. Think about it, how many people are buying > $350 GPUs daily? The bread and butter of GPUs is in the < $350 space. With < $100 GPU market mostly killed, it's really even worse than that. Still, AMD has that covered with HD7750/7770/6850/6870/7850/7870. NV literally has nothing worth spending $1 on in the < $350 price range on the desktop space. So it's doubtful desktop HD7000 series is the problem here.
I think the Mobile Kepler design wins all over the place might have clawed back some discrete mobile GPU market share from AMD.
However, if anything, weakened growth in the China and emerging markets probably hurt uptake for Trinity platform (not to mention it was delayed), servers, etc.
Also, I haven't recommended a single AMD desktop or mobile CPU to anyone I know since Bulldozer launched. If you want to honestly point the blame on why AMD is doing so poorly, lack of smartphone/tablet CPU strategy and terrible execution on Bulldozer and Llano/Trinity are the answers to most of that imo. Like I said before, Bulldozer is such an epic failure, AMD would have been better off shrinking Phenom II to 22-32nm and pumping clocks to 4.5ghz. It would have mopped the floor with Bulldozer in performance and power consumption.
Rory said the new strategy is attacking emerging and less lucrative markets where Intel doesn't want to go but all these delays for Trinity platform haven't helped. Further, the Ultrabook competitor from AMD is still MIA. Their strategy for undercutting Intel's Ultrabooks with attractive Trinity laptops so far hasn't been materializing. What AMD has launched so far are awful budget laptops with crappy keyboards, cheap screens, half working trackpads and thick plasticky shells.
The sad part is they are going to be 1-2 generations behind Intel in CPU performance unless something unexpected happens. Piledriver claws back 10-15% CPU speed, well Haswell will extend IVB by 10-15%, ad infinitum.

In the desktop CPU space, AMD is behind not only in performance but also in power consumption.