It's an arms race in the GPU market too. Given the relatively MASSIVE efficiency improvement nVidia have brought with their Maxwell architechture, AMD will hopefully be following suit, so the next or next-next line will be mining the same hashrate for much less power too. That's what happens in the tech industry, things are out-of-date really quickly on the enthusiast end.

I've start mining again when it's cold, it's a heater that helps pay for itself.