I have't been using Linux for very long but I like it a lot so far... It gives you so much control over everything. In Windows, a lot of stuff is automated and behind the scenes but in Linux it's all right in your face and highly customizable. At first it can be pretty overwhelming but as front2back said, once you get the hang of it you won't want to go back. And of course there's the fact that it's open source so there are tons of distributions out there (unlike Windows where there is just one version). You can select the one that suits your individual needs.

Good luck in Linux
mjk