I recommend an Intel Core i7-930 Bloomfield quad-core chip.
The price point on those is excellent and the core is unlocked so, with a motherboard that will let you, it is possible to overclock it and easily achieve speeds that cost 4x as much or more. Note you will need a good heat sink to overclock realiably but with a good one people are getting 4 Ghz out of them (or better with super cooling setups). Even with a passable heat sink you can get 3.3Ghz which if bought costs 3x as much.
Really great chip.
Note the above is a Bloomfield core so you’d need a mobo that supports Socket LGA 1366.
Also note that this chip supports triple-channel memory setups. So if you get it be sure to buy three sticks of memory (and a mobo that supports it). E.g. Buy three sticks of 2GB each. They are sold this way now.
If not that then get the Intel Core i7-860 Lynnfield 2.8GHz
Not as good (and only barely cheaper than the Bloomfield chip) but more common these days and does dual-channel RAM. It runs on a socket LGA 1156 mobo.
The Bloomfield chip is only about $80 more than the chip listed in the OP and easily surpasses it. Well worth the extra money IMO.
And skip a dual card video setup unless you are rich. Getting dual cards will mean you have to pay a lot closer attention to heat issues as well as power issues for a not super-great jump in performance (if you have dual monitors or more than a dual GPU setup starts making sense). Best bet is to get a solid (1-2 steps back from top of the line) video card. If you want you can buy a second one in the future to keep the machine banging along or just get a whole other video card. Not all mobos can do this either so pay attention to that.
I run a Radeon 5870 and it plays just about everything at max settings at 1900x1200 (Crysis would push it a bit hard).
Some of the new top of the line cards are very long. Be sure your case can fit it.