TPU
The 580 is now noticeably faster than a 5970 up until 2560x1600. Not too shabby
That's because in more modern games like Metro 2033, STALKER, the scaling with the
5970 is sub-optimal. Also, it seems the lack of Tessellation performance of HD5870 series is at least partially to blame. Also, keep in mind it's a bit unrealistic to start comparing a 1.5 year old HD5970 with inferior HD58xx CF scaling to the 580. If you were in a position to spend $500 on a graphics card setup today and were open to dual-GPUs, then the GTX580
should be compared to the most modern $500 setup - HD6950 2GB CF - since its priced comparatively. In that case,
the 580 is a sore loser (that's not even considering unlocked 6950s). And once you get to 2560x1600 resolution, that ~20% performance advantage the 580 has over the 6970 is
eroded to only 3%. That's pretty sad for a card that costs a whopping 58% more.
GTX580 vs. HD6970 is GTX285 vs. HD4890 all over again. You get the GTX580 now for $490 vs. HD6970 for $310 for that extra 20% performance increase up to 1920x1200. In late 2011/early 2012 when 28nm GPUs are available, the HD6970/GTX570 user can just sell his/her card and use that extra $180 "savings" towards a new GPU that will mop the floor with the 580. The 580 really is targeted at price inelastic consumers.
It's nice to see MSI push the engineering envelope with both cards though.