I'm also thinking of going with the 8800GTS. Its just that I need a new graphics card anyway.... and I was thinking of getting a cheaper card and then upgrading to DX10 next year. But unless I spent about £150, the cheaper card would be crap for gaming and I would be buying a srubbishrubbishrubbishrubbishy new PC and then playing it with low-medium settings until I upgrade. And then when I upgraded the £150 card would go in the bin
So I decided to spend about £150 more and just get a good 8800GTS.
My only concern is that it will be an amazing DX9 card, but it may struggle with DX10 when it finally shows up. And after spending £300, I'm not going to want to upgrade to the later version of it, or the ATI R600 next year. So its quite a big risk, but I'm 99% sure I'm going to do it anyway.