Don't hold your breath for the 9800GTX it isn't next gen, it is g92 based tweaked and improved, from what I have read.
The GX2 is basically two 512 GTS in sli so it will perform nicely. I can't see nvidia pricing this much higher than the X2 as the X2 is the GX2's competition. Mr. Smith estimates £325ish. Obviously I could be wrong.
Y'know what is getting me excited? No upcoming tech. Not this year anyway lol. Crapola multis on the new intel quads (bar the uber expensive qx), none existant competition from AMD in the cpu market and rehashed gpu tech from both sides.
Smith out.