This thread is almost the same title of an article I just wrote!
Instead of the 285, I pitted the 250, 260, and 470 up against one another (I wanted to have an entry,mid, and high-end test).
I tested all three cards (EVGA versions) in a Core i7 rig w/ HAF-922 case. As virrze said, the 470 runs hotter, but it also does a lot of 2D throttling.
Even if you combine all the benchmark scores for the 250+260, the 470 is still higher. But if you want to spend about half the money and still feel good about your purchase, I'll say the GTX 260 Core 216 55nm was my favorite. I found it ran very cool and has the most overclocking potential.
I extensively benchmarked each card separately and also combined all the results in my head-to-head article at Link removed.
Here's a Solid Tip: If you go from a 200 series to a 400, don't try to swap cards and reboot. The 400 series has their own set of drivers. I muddled for an hour trying to find out why Windows kept saying "Standard VGA Graphics Adapter"!