Is there any advantage to matching up GPU and CPU? Was checking out the specs for the 280x and there is just so much AMD tech listed it makes me wonder if it would perform better with an AMD CPU over an Intel. Especially with talk I've been hearing that games are going to start making better use of all the cores. I was going for an Intel build buy now I'm reconsidering the whole thing.

nope, no advantages

Some people think AMD's drivers prefer Intel (ie are more optimized for single threads), but I don't know if that's true.

It honestly doesn't matter. It really depends on what you need (whether your software or choice of games are optimized for single thread performance or multi-thread performance. Intel is very good for either, but most notably for their per-core performance) and how much money you can afford to spend (with gaming and everyday computing tasks, AMD typically offers better value for the performance.)