This is pretty hard to define for me. At work, I primarily use Windows 7. My away-from-work computing is pretty evenly split between my laptop (MBP running Lion

This is pretty hard to define for me. At work, I primarily use Windows 7. My away-from-work computing is pretty evenly split between my laptop (MBP running Lion) and my desktop (custom box running Ubuntu 11.10). I'd say my time pretty evenly split between all of these operating systems. I think I prefer Ubuntu overall, however the ease of use of OS X and Windows 7 are pretty tempting a lot of the time (try installing Spotify on Ubuntu 11.10 and get it to play local files). I'd probably prefer OS X among those 2, though since it's much better for development. However, for the most part it really doesn't matter what operating system I'm using.