The 7970 is supposed to be comparable to the GTX 590 and Radeon 6990. You should only need to wait a few more days to find out if the 7970 will live up to the hype. I think it will but don't guarantee it yet, remember how fast bulldozer was supposed to be. If you look in the benchmark picture on the page you would notice that for most of the games the 7970 was at or above 50% faster than the GTX 580 but like the article warns AMD may have inflated these numbers.
More info on Softpedia about AMD's 7000 line up including the 7900 cards:
If there is one thing AMD are good at is graphic cards.
Impeller fans are the fans on that graphic card like a cylinder. They are OK, tend to be loud and my gcard died due to dust build up.
HD7970's are definitely worth the wait. if 7950's are $300 a peace buy two of them and you'l be good for years.
i5 IS good for gaming but future proof with i7.
I made the good choice of going for a q6600 when the Duo's where "better for gaming".
My reasoning against getting the i7 for future-proofing is that Ivy-Bridge comes out next year and will have significant improvements in performance per watt and considerable performance improvements supposedly without increasing cost.
Ivy-Bridge is supposed to max out at 77w TDPs (compare to SB's maximum 95w TDPs) yet out-perform similar Sandy-bridge CPUs by 10-15%, possibly leaving extra room for overclocking.
The 580 is (until the 7970 comes out in a few days) the fastest single GPU video card on the market. No other single GPU video card comes close to it. However, for it's price you can grab two Radeon 6950s or two Radeon 6970s, crossfire them and have a much faster setup.
Technically two Radeon 6870s together are faster than a single GTX 580 but there are problems (micro-stuttering) with crossfire at high settings with anything that isn't a 6900 series right now.
The 580 is great but for it's price it is lackluster compared to other offerings that would have much better performance.