I don't think we're on the brink to changing from dual to quad cores, because the vast majority to people are not going to notice the difference. No doubt, we will someday all have a quad core chip in every computer, but right now, it's just not going to happen. A dual core CPU is capable of handling everything 90percent of people are going to do with their computers.
In your case, the choice is all yours. I'm willing to bet that there is very little difference (while running most applications) between the 2.53GHz Core Duo, and the 1.6GHz i7 CPUs. I've got two of those 2.53GHz chips in a couple of computers, and they are extremely fast. However, Intel seems to be trying to make the i7 and i5 CPUs the "future", so you might be 'up to date' for longer if you got one of those.
Im looking to buy a new laptop and am not sure about getting a duo core processor or a new i7 quad core processor. I wont be doing any gaming but would like a very powerful/fast computer. My concern is that a lot of software at this time wont take advantage of the quad core technology. Are we on the brink of moving from duo cores to quad cores or is there still some time? I've been looking at:
Intel Core 2 Duo 2.53 Ghz, 1066 Mhz FSB, 4 Gb RAM
Windows 7 (or pay the premium for Mac)
vs
Intel i7-720QM 1.6 Ghz, 4 Gb RAM, with Hyper Threading DMI Bus type (I have no idea what that even means)
Any advice/opinions would be greatly appreciated. Thanks in advance!

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