In older games it should be fine at higher resolutions actually. I have targeted this card since word first leaked out. I had a HD3870 for two days, it was Rev 3 meaning it had the Zero Thermal cooling solution which was much too large for my narrow mATX board, I had to remove a tuner card.
However Aaron is wrong, I found that HD3870 from a link on Slickdeals.net It was from Micro Center here in Southern California. It was $119 before tax. I have NOT found one that is the original ATI reference board that I know will fit my motherboard for under $130. The HD3850 can be found for under $100, but this will eat it alive.
I could afford a HD4850 but I don't play games on a PC often enough to spend that kind of money for basically part time use and reduced use in 6-8 months down the road.
ATI also announced a few weeks back they are stopping production of the 3xxx series all together, so whatever is out there now is out there. I can't find another HD3870 for under $130 out the door, true single slot. Even so, turn on the filters and the FPS will drop, not so with the HD46xx cards and two HD4670 should beat a HD4850 and give a HD4870 a run for its money. Given the cost of the 9600GT at around $130, I would expect the HD4670 to come in around $10 less no rebate which would put the decision on the person buying, do I wait for the rebate on the Nvidia and pay $130 now or do I get the newest ATI "budget" card for $10 less no rebate involved and I assure you performance is close if not better than the 9600GT.
When we'll you guys get a test sample to put it through its paces and PLEASE test GRID with it. That's what I'm getting this card for...