The card companies know how to price their stuff. The expensive cards always look very tempting, the cheap cards cheap and the mid-point cards cost-effective.
Also, while new cards coming on the market make the prices of old ones drop, they know to drop the price just a little initially to catch the price-conscious but impatient buyer. I'd guess it'll be Mar or Apr before you see nice discounts on 5870s.
Whatever card you get, it'll still give the same graphical quality in a few years; games move on but cards don't go backwards.
I'm very happy with my HD5870. I'd advise a cheap vanilla version; I can get 915 MHz Core/1310 MHz memory from mine without overvolting using MSI afterburner which works with non-MSI cards as well. A slight overvolt allows 930MHz core or so, but that's the limit pretty much and another card might not even make that.
This O/C gives +7.3% on Furmark 1.8.0 with post F/X and displacement mapping active, +9.3% without them. That beats many of the higher priced versions on the market. I don't run the o/c normally because it's not needed, but there's a little overhead there even if it's not as much as the 5850.
MSI Afterburner + HD 5850 should get really nice performance. Edit msiafterburner.cfg to read:
Code:
[ATIADLHAL]
EnableUnofficialOverclocking = 1
and it'll allow you to go past the BIOS-specific clock limit which is restrictive on the 5850. There's no risk of damaging the card unless you do something nuts. I'd never o/c'd anything before Feb, but there are simple guides on the web.
dduff