At the office, I'm on Win7, which actually isn't too bad for Windows. With it I run WindowsPager to get multiple virtual desktops. It's reliable and pretty solid.
That said, at home I now have Macs. I got tired of testing a half dozen Linux distros every six months to figure out which one will work on the current update. OS X is solid, and I can do anything I want with Unix, supplementing with MacPorts. Not only can I work, I can haz fun.
I have work to do. Windows is lame; Unix is easy.