True Bomb, very true. But one thing my conversations with Jim Prior have it made crystal clear to me is not to expect any future mid-range to high end flagship CPU's from AMD that do not have an iGPU on them.
So in that light, even taking HSA's worst case scenarios into mind, FM2+ is still the way to go if you intend to stick with the newest AMD chips down the road.
Please keep in mind folks, the end game of Kaveri (and especially Excavator a year or so from now) is not for these APU's to fall into the midrange class. AMD has stated numerous times the chips without proper acceleration will lose to haswell in most cases and we have indeed seen that play out in numerous programs and apps.
The end game is to change the way devs approach coding altogether. To stop using integer cores in situations that integer cores tend to suck wind at. If they have their way, this 7850k will likely fall between a 4670k and a 4770k in anything using HSA acceleration, and Excavator may indeed greatly supercede that.
If they don't have their way, well, it was a noble effort. Either way my point is that we still know absolutely nothing about this chip'spotential performance. Gaming wise, Thief will be the first game to give us a really good idea of it.
Benchmark wise, I'm hoping Futuremark and/or Uniengine recode to demonstrate what an APU can really do, but that is a fingers crossed thing.