i dont use linux as a full time desktop just because i dont expect it to run the windows applications i use frequently but some times randomly
some times i can use linux for a couple days straight without needing a reboot, some times i boot up into linux and want to use something i have a tool for in wndows with no linux equivilant and end up rebooting in 5 minutes...
linux has its place in my heart, i honestly love teh system i love tweaking with stuff, i love the security side and some of the amazing things you can do in linux that just arent possible or are much harder in windows... but for my desktop ill run windows
i use linux for specific stuff, like i can use grep to find poorly named files created by programs even if they are binary files (did this to find certain 1v1 match demo files for quake that were time stamped but not named by opponent), and i use backtrack frequently for lots of security and professional needs as well as to scratch my penetration testing itch for knowledge
linux as far as an administration view point is muuuuch better than windows in my opinion, any server i run will be linux, and i much more enjoy dealing with more advanced administration in a linux environment
even with how much i enjoy linux and value its uses, for a desktop i will still and probably always will run primarily windows