12 Jan: Ferrari
15 Jan: Toyota
16 Jan: McLaren
19 Jan: Renault
19 Jan: Williams
20 Jan: BMW
9 Feb: Red Bull
2-4 Mar: Force India
Torro Rosso: unknown
Honda F1 future unknown
I dont know about the X2 but the 4870 runs extremely hot!
I wouldn't be surprised if the 260 passes the 4870 when both cards are overclocked. I'd put that into consideration when buying, especially since the GTX260 is now the cheaper GPU to buy.
edit: Interesting read. These new driver's from ATi and NVIDIA makes this comparison worth a re-look