At $300 that 7870 is looking delicious, but I'm not sure I'd be willing to pay that for it.
I dunno, think I'm kinda' biased. I got this 5870 so cheap yet I'm so pleased with its performance. I almost don't want to upgrade because of that. Really don't think I'd feel the 7870 was a $300 upgrade over my 5870, if that makes sense.