Nice system list you got there. I would like to suggest a couple of modifications if u don't mind:
Go for a TRUE Black or a Noctua U12P. Keeps that hot i7 chip cool and allows for some nice overclocking.
Go for the i7 920 D0 stepping - for lower voltage operation and overclocking.
The GTX 275 looks like a great card, if u eventually decide to go SLI, you should be beating a gtx 295.