There is shortage of chips from AMD (ATI), they had to increase prices.
Also, I second the opinion about RMA not being a big issue. I've never had to RMA either of my 9800Pro, x800Pro, 6600GT, 7900GS, x850XT, x1950Pro, HD3850, HD4850, or current HD4870. All cards have been used for at least 1.5 years, have been voltmoded, overclocked, heatsink/fan swaped 3-4 times. All older cards were always returned to stock and sold on eBay. Still own the last 2 in the list and the 7900GS (4850 is 2 years old now. It and the 4870 are under voltmod with Accelero S1 + 120mm Scythe fans. 7900GS is voltmoded, under VF900-Cu). Of course, manufacture defect is always a possibility. However, I believe most video card failures are user error (bad power supplies/electrical in the house, poor ventilation, dust, etc.). Now, if you know you're a noob and kill hardware all the time, go with XFX, BFG, eVGA (only the first one makes cards on ATI chips though), best warranty in the industry.