Believe it or not, that isn't true. I bought my Radeon 9800 Pro (256MB DDR) about 2.5 years ago, and its still pretty damned good. Mind you, its not the best, but I have been able to run every new game on pretty much all the highest graphical options (or near highest). And I only have a 2.2 MHhz with 1GB DDR. So, don't discount the new stuff as old a day later.
That doesn't mean to dump an asston of money, either. I'm just trying to illustrate a point. It isn't quite as bad as they say, is all.