7970 pricing is weak relative to GTX 670.
I can't comment on firsthand AVsync performance obviously but it sounds good in theory anyway.
I don't miss Physx/CUDA but then most people probably wouldn't miss the extra 1GB VRAM going from 2 to 3, either.
A GTX 480 for compute? No thanks, that thing is a power hog.
I don't see what controversial about what I wrote. The GTX 670 is obviously the price/perf winner in the $400-500 bracket though for top single-GPU performance it trails the 7970/680 by ~10% when all are max overclocked. The 7970 is priced higher, but if you sell off the extras it actually isn't as much of a price/perf drop relative to the GTX 670 as one might think, though it does eat more power. And the GTX 680 is like a more power-efficient version of the 7970, at least at load, but you pay extra for that efficiency like you pay extra for a 80+ Gold rated PSU over a regular 80+ rated PSU. Many people with access to cheap electricity don't even bother getting Gold rated PSUs because it takes a long time to recoup the costs for them, but for others it could matter more. The other stuff like +1 GB VRAM, Cuda/PhysX, HPC performance, etc. kind of cancel each other out for many people.
EDIT: Wow, you can get a 7970 reference for $435 after rebate. Sell off the extras (cable, games) and it could actually be less than $400 for a card that edges out a GTX 670 (stock vs stock) and is about 10% faster (oc vs oc):
http://www.newegg.com/Product/Produc...82E16814161399