4x400GB Seagate 7200.10s?
Overkill?
How much storage you need?
Oh yea, you have the raptor too.
You better be running those 4 drives in RAID5...
Anyway, it's gonna be a few months before we see anything definitive about the R600 (i too am eager to see how it performs).
I don't trust that one site that posted the benchmarks. Probably fake (hell, if they break the NDA, why not just go all out and post the dam pics of the card

)
So, what monitor you have (what resolution you gonna run at)?
And I'd say if you have the $$$ to get everything else in that rig, then why not just go all out now. Get an 8800GTX.
The drivers are finally starting to slightly mature a bit (97.92 release) but they are no where near fixed yet (although I haven't encountered a lot of these problems.)