I'm building a comp right now and watch your cpu sockets intel offers both a 1156 and 1366 sockets. I running a i7 920 and its the 1366 socket along with the 950 and 975 where as the 860 and others share the 1156 socket
If you go for the Core i7 you might have to modify your motherboard as it can break otherwhise, the temperature on the IOH by default is skyhigh, with some bending and twisting you can mount a new cooler on the IOH tho, easiest done while building the computer. My IOH with original cooler went up to 94C, that is not acceptable even if its listed as 105C maximum. Anything above 95C will slowly damage your components. After getting a heatsink from thermaltake its now at 52C while playing, much better and far from the max temp.
I dont know if they have fixed this on the new motherboards, I bought my computer 5-6 months ago, but from what I can see they are still using small heatsinks that is covered with the brand of the manufacturer, that is horrible to cover a heatsink as it traps the heat inside.
If you still want to go for a Core i7 I can show you pictures I took while I was removed the original heatsink and installed a new better one.
But, to be honest, the CPU aint the highest priority here, what you want to put your money on is the graphics card. If you can wait 1 month, or maybe 2, there will be new high-end cards in the 300 series out on the market. Get the GTX 375 card, most bang for the buck and it will surely run STO at highest settings.
Dont remember to get a good case for the computer, you need alot of airflow with a Core i7 and/or a high end graphics card.