Windows XP is a good OS, but I don't like the direction which Microsoft is going. I like to control my computer. I don't like to have things shoved down my throat, and I certainly don't like anybody snooping to see what I have on my machine.
This lead me into exploring Linux more in depths. And I am very impressed. My next task will be to install WINE and see how well it runs the couple of essential Windows programs I use (mainly Dreamweaver and Flash). If this is conclusive, I may actually only keep my Windows partition for games (then again, I heard of people who can even play Direct X games over WINE).
The interface of Red Hat 8.0 is just awsome. It has animations, mouseover effects... Very nice.
Oh, and did I mention it's a least twice as fast as XP? (on my Celeron 333 / 128 megs of RAM)