Just switch. 
Why? What is so great about Mac's? Doesn't everybody just love Vista? 
Honestly? Vista is okay. I had to turn down all the "candy" on it for my laptop though (a brand new one by the way with a dual processor and updated graphics card) and had to buy 2 more gigs of ram for it to run smoothly. Most people who don't like Vista really just don't like Microsoft at all. I have both in our house. I have to use Microsoft because of some compatibility issues with some programs we use for "work". I also do have a personal issue with Vista wanting to update it'self all the time, but I get over it quickly (like I do most things). My wife prefers Windows, but only because she's never known anything else.
I prefer using Linux at home only because I don't like spending oodles of money on Microsoft products. Linux itself is just a download as are the majority of programs it runs. Anything else I can load in wine unless it's graphics intensive.
Mac is a good platform for graphics and other things, but most people who use it today, do so because they were either raised on it, given one by a friend, or just really like it.
It's all just personal preference and not much else.
