Seems like a decent build, but remember a few months is a lot in the PC market, by then prices will have dropped - especially on the CPU what with quad cores coming down in price. Also by then
Crysis will finally be out so you'll may want to consider a DX10 compatible graphics card like the 8800 (remember they will be cheaper in a few months!)
If you want to save a bit you could always buy a graphics card second hand from ebay - since gamers are always updating their rigs you can find some nice bargains on there. A few months back I bought a 512MB 7950GT OC on there for £100 (they retailed for £150-160 at the time).
Also keep an eye out on sites like hotukdeals.com - they list good deals on products ~ I picked up a 20" HP monitor (L2045W) a few months back for £125 (RRP £175-190) as HP were offering a £50 rebate at the time.
Personally I would lose the cooler and splash out a bit more on the case - a PC deserves a good case, especially if you plan to overclock. I have a
Antec Nine Hundred and I can honestly say it was worth every penny. I have an E6300 overclocked from 1.86 to 3Ghz and it's running at 40°C on stock cooling with case fans on their lowest speed.