key issues to look at when comparing..
Memory controller 256bit / 384 /512 ? = important issue !
Memory Size = not too big an issue i think.
Stream Processors = BIG BIG BIG issue.. the corresponding R line matching the 7 series have more (but cost more and may not have fans as good)
shop around and you'll see prices are the same everywhere.. i know of no specials deals.. these cards are in HUGE demand.
i have been studying these models long and hard for a while now and have been buying my own gpu's for more than 10 years
if you want i can post a break down of what R series card match's what 7 series card if you really want ?
quick advice is go with a 7950 or 7970 with dual fan's or better.. although a lot of the 7970's are too expensive i think
Stay away from 7870's they have a 256bit mem interface and way lower stream processors, you might as well spend the money and get better..
or
Go with R series cards (again NO single fan default ref design setup)
and like the 7970's stay away from the R 270x line they have similar specs to 7870's.. once again a 256bit interface and lower stream processors
the R280x is medium range and would be the match for a 7950 BUT the new ones have more stream processors so should hash faster (compare prices to 7950's)
the R290x line is like 7970's the have an even higher Stream proc and higher em interface (for mem bandwidth improvements)
I see some 7950's for 250 (almost 300 after taxs / shipping etc) and may grab one soon but that may change i am not expecting money for a week or two maybe
by then things could change or stock could run out, such as if the 280x's drop in price a bit i would go for them instead.
Also one last thing.. if your picking one out don't bother with single fan reference design fan setups.
and even more important to me is don't buy one with the damn connector grill with connections blocking the out-take air ventilation ..see picture
