OK, so I installed the Arctic 7 Pro cooler and I am exporting Sketchup right now and CPU 1 and 2 are both reporting 55 C under full load. This is an easy 10 to 12 C drop in temp. I know the big CPU towers (tuniq tower etc.) cool even better but I wanted a low cost no-motherboard-removal solution, which this is. It just snaps in place of the stock cooler. It is quieter than stock too I think, but my RAID cage makes a lot of noise so it is hard to tell how much quieter.
Just thought I would share since a lot of people have been wondering about heat and Core 2 procesors with their hackintoshes.
*update-- I went ahead and overclocked it to 3.1 GHz from stock 2.6 and it is sitting ~60 C on both cores under full load. My test file dropped from a render time of 41 hours at stock speed to 36 hours. That's sweet, and still about 5 C below where I was at stock speeds on stock cooler.