As a guy with a Phenom x4 9950@3GHz who previously had a celeron dualcore E1200@3.2GHz, I wish to say that your statement is total crap. Hell, I just built a system for someone with a Sempron 140 2.7GHz single core or whatever the hell it was and it loaded up the windows 7 installer just fine.
Damn man, the Turion x2 RM-72@2.1GHz in my notebook loads up the win7 installer just fine. That being said, I have never had to do it more than once on any of that hardware.. but still.

You do know that a 5870 completely smokes a gtx260, right?
Except that what you have stated was not "preference or taste", it was total garbage related to the performance of something. There is no "preference or taste" there. One is faster than the other and that is that. Liking one more than the other does not make it faster.
It is _very_ different.