I think BlackStar's point is still valid at the very low end, particularly for people coming from an older AMD build, and just dropping something like an Athlon II X3 435 for about 70 USD (apparently it can OC easily to 3.5Ghz).
For any of you following the best gaming processors in the monthly analysis from Tom's hardware, I think Intel will take over everything but the very low end.
It's funny though. We are calling a triple core @3.5Ghz "low end" these days. Just 10 years ago that was pretty much a mainframe :)