Spyware was the last straw for me. I ditched my PC and bought an iMac and have not regretted it one whit since. I just use the thing and no more playing cat and mouse with all the crap on the internet. I could care less about brands and loyalty to companies so don't start the harang about Macs. It just works and that's all I care about.
Apparently you haven't spent a lot of money on software for the Wintel platform (games, utilities, applications) or you wouldn't have so blithely marched into the Mac camp. Many of us have substantial investments in software that we aren't willing to give up just for the honor of spending too much on a computer that doesn't require you to think too much.
Personally, I use Windows for games and applications then switch over to my Linux install when I want to edit sound or video or surf the 'net or open up any other kind of hole in my shields.