I know that this is an old topic, but wanted to comment that I've finally decided to go for Intel and acquired Core i7 2600K. The budget got very restrictive, so I've got Asus P8H61 mobo and cheap RAM (will get better parts later on). The original Intel cooler was too crappy so I've used CoolerMaster Vortex Plus (even though I don't like it due to large gaps between heatsink and heatpipes on the side touching the CPU). Anyway, the performance is roughly 3 times of my Q6600 and 2 times of my mobile i7 840QM.

However, even though Core i7 2600K has lower thermal profile of 95W when compared to Q6600 having 105W, it runs significantly hotter in stress tests.