think about it like this: you've used it so long, might as well use it for a little longer. buying computing hardware is always like this: if you don't buy when new generation just come out, might as well not buy until next generation.
I used to think that this kind of approach was ludicrous, but recently I've come to agree with it; within reason. Just look at the lasting value for money early 8800GTX adopters got just a few years ago..
But then you're always buying at the inflated early adopter prices I tend to buy a mid-range card when they come out and the prices have dropped a little, I don't think I've ever owned a top-end card from either manufacturer. I'd love to know what thought process went into upgrading to SB yet leaving the 3850 in there
well, what i should have typed, but couldn't be bothered is: buy after all companies have released their cards, and around a month afterwards when the prices have settled down. don't buy when the product life have gone past 1/3 of its life cycle. eg. don't buy current generation GPU now, sandybridge is on the boundary of buy/not buy. iPad 2 is also on the boundary if they stick to their 1 year update rate. iPhone 4 is a definite no-no at the moment.
I don't know how you live I take this attitude but I would like to give crysis a run through, max out Serious sam 3, be ready for BF3 and at least run my little baby shogun 2 at high settings with DX11 shadows. I think I'll just get the best performing card at £100 then save my money for untill southern islands comes out. I like the look of that 5850