I love the fact that AMD continues to push the bang for your buck barrier. I currently have two 6970's and they work beautifully, but I definately always am looking to always have the latest and greatest, at the best price to performance ratio. My AMD cards stay nice and cool while always delivering excellent performance. Can't wait for the next upgrade!
I have been using my 5870 for eyefinity gaming across 3 screens (3600x1600 portrait mode) since the card was available. Even now, that card keeps up with the games I play most often, especially LOTRO, with all the options cranked. There is just no substitute for the situational awareness you get from that much screen space.
I'm impressed by the performance improvements that new drivers have brought to the AMD 7000-series GPUs and would love to experience their abilities for myself.
I've been using ATI/AMD cards for years. They're powerful, fast and overall seem to last a really long time. They're also by-and-large more economical than their competitive counterparts.
I enjoy the value of AMD products.
As many have stated, the price / performance ratio is fantastic and the added incentives such as free bleeding edge AAA titles add increadable value for your money.
I have used AMD/ATI cards since the 9600 Pro. I have always been impressed by the performance for the dollar. A 7870 would be a nice upgrade from my 6870.