I can't seem to decide between the following systems. Both are 27" iMacs. i5 Option ($2050): 3.60GHz Intel Core i5 4GB 1333MHz DDR3 SDRAM - 2x2GB 1TB Serial ATA Drive ATI Radeon HD 5750 1GB GDDR5 SDRAM i7 Option ($2200): 2.93GHz Quad-Core Intel Core i7 4GB 1333MHz DDR3 SDRAM - 2x2GB 1TB Serial ATA Drive ATI Radeon HD 5750 1GB GDDR5 SDRAM So they're pretty much identical except for the processor and the price. The new i5's have both hyperthreading and turbo boost just like the i7. So it seems like I'd be paying an extra $150 for 2 more cores of comparable quality. Seems like a good deal! However, the i7 clock speed is 20% slower, so for many apps that don't utilize multi-core very well, the i5 should be significantly faster. Furthermore, for the apps that do use multi-core well, performance may suffer a bit since I'll have less memory per core and would likely have to buy an extra 4GB Ram soon (my rule-of-thumb for the last 4 years has been 2GB/Core), raising the price by another $140 (crucial.com). So right now I'm leaning toward the i5. On the other hand, I'm not going to be able to afford a system like this for at least another 4 or 5 years, so maybe the i7 will keep it going longer? Any other differences between the i5 and i7 I should be aware of?