Do I upgrade now or wait?

People...I havnt had a decent gaming pc for almost 2 years now, I had an P4 2.8Ghz,512mb DDR266 (I know its disgusting!), 160gb hdd,geforce 6600 256mb.. The pc played CSS and all games I wanted on low detail,so I could atleast njoy myself at LAN's... but im finishing my MCSE in november and I wana reward myself with a nice pc :-) I was thinkin in the direction of:
AMD x2 5200+ dual core
4Gb DDR2 800
320Gb SATA2
Gigabyte SLI mobo
500w dual rail PSU

and a Geforce 8800GTS 320mb

This rig will fit my pocket quite nicely and Ill be able to run Vista and all the new DX10 games (I hope).
But the problem Im having is this: Ive read on the net about the Geforce 9 series being released in November/December and that the new cards will all support 10.1,and the 'old' geforce 8 series cards wont support the new DX 10.1 features... And also that AMD is releasing the new Phenom CPUs.Now I know you can never keep up with technology but I atleast want to get the PC that will last me the longest before my next upgrade,I wana be able to play Crysis and Bioshock and the like with decent quality graphics settings... Is this maybe too much to ask from the above pc? Do you guys think I should wait another month or two or should I go ahead and shop in November?...

I'd say go for the 2900pro. They cost around £165 and are a good match to the 8800gts, however early indications show people have overclocked these to 2900XT speeds or higher and support DX 10.1