<- doesn't know jack squat
Has it been confirmed that they're doing a 28nm shrink of ... Piledriver (I assume?) And do you happen to know if it will be GF or GL? (And built by GloFo or TSMC?!)
I don't know any more than the rest of you. There's those AMD slides out there in the wild which refer to a 28nm refresh of the non-bobcat x86 stuff.
Given the questionable economic viability of GloFo pursuing development of high-performance SOI solely for the sake of one customer (AMD)...and given the undesirable effect of AMD being locked into using GloFo as their foundry so long as they (AMD) avoid bulk CMOS for advanced x86 designs...it only stands to reason they (AMD) would be divorcing themselves of relying on SOI-enabled nodes while simultaneously directing GloFo to not waste precious limited R&D $'s on developing a specialized SOI flavored 22nm node just for AMD's benefit.
(When I was at TI we had many such MOA's - memorandum of agreement - between ourselves and SUN...for example we had a High-K program for SUN at 90nm but they didn't want the associated cost and we didn't want the associated disruption to the rest of our CMOS integration in the fab, so we both agreed to shelve it in the meantime for 90nm and 65nm, focusing on improving the traditional poly-si xtor tech for both performance and cost reasons)
If such a divorce from SOI is coming at 22nm then there is no reason to not take advantage of the forking even sooner, and 28nm at TSMC makes a lot of sense in this regard because that is exactly where SUN (Oracle) is having their next-gen CPU's fabbed (so TSMC is already well invested in developing a higher performance subnode flavor to SUN, AMD could have given them (TSMC) even more motivation by signing up for it as well some years ago).
That said...there's a lot of potential fallout from this. Soitec's business model will be utterly destroyed if GloFo stops employing SOI in future nodes. And GloFo's own viability as a foundry would be all the more in question were AMD to field a 28nm high performance (flagship type) product from TSMC as being the successor to the existing 32nm product coming from GloFo.