They say plasmas last like 6 years I think before the backlight gets to half of full brightness. I'm sorry I can't actually claim that as fact, since I'm not really that interested in plasmas anymore, but I thought I heard somewhere that 6 years was abou the average. I think LCD panels have a much longer lifetime, which is why you see them more for displays at airports and bus stations and the like. From what I can tell, the bigger Sharp Aquos LCDs equal or beat that plasma in almost every category, except size (either 45" or 65".... 65" is outta ur price range). Samsung and Sony also make some big LCD panels i think, maybe up to 50" now, I don't know.
I don't really have any intention of persuading you to buy something besides plasma, but what are your reasons for choosing Plasma over the other displays out there (DLP, LCD, LCoS, etc.)? Just curious....