..and the 7970 isn't much fater than the 580. There is approximately the same performance difference between a GTX570 and 580 as there is between a 580 and 7970.
@stock yes, but oc both of them there is a big difference, we all know that and nearly everyone that gets one that reads here will oc it, you can be sure of that!
The 580 is now overpiced for a last-gen card, and is only maintaining it's price because the 7970 is neither massively faster, nor better overall value in terms of performance per £. Out of the two I would swing towards the 7970, but that doesn't make it worthwhile. I think the 6950 is the only gaming card really worth buying at the moment.
They are both massively overpriced, the 580 hasn't been reduced because they are eol, it's simply went back to the rrp rather than price gouged.
Nvidia is quite happy waiting for the diehards to purchase dwindling stocks.
Neither of them are worthwhile as they could/can both be bested by cheaper twin cards.
I have been using 6950>70 CrossFire for over a year now at a cost of less than £400, almost double the performance, on occasion more than double and cheaper than what the cheapest 580 was at the time@£447 much the same as the 7970's are now.
Even if they didn't unlock I would never have bought the 6970 or the 570/80 as performance gains are terrible for the price you pay, been their done it, won't get another t'shirt.
Considering oc'd 580's were/are not much faster than oc'd 480's, Nvidia still sold lots of them, the same way AMD will sell lots of 7970's which are considerably faster than 1 69** but slower than 2 69**.
Imho, it seems to me that you are on a one man crusade trying to stop folks purchasing the 7 series, your fighting a losing battle as they are selling, they may well not be flying off the shelves but they definitely are selling.
At the end of the day folks will purchase them no matter what you/I/others say, that's the nature of the enthusiast market, some will even ditch their 79** to jump straight on Kepler
if it's faster.