I use Linux daily and very heavily. I administer and use it on a 300-core compute cluster, I develop applications on it, I maintain packages for a Linux distribution. I guess I have a lot of use for the environment.
I also need my OS/DE/the whole stack to support my hardware well without spending days tweaking it and to provide me with a GUI that doesn't suck. It does so perfectly on the cluster/server, but is pathetic at it on my laptop (it's a Thinkpad, so the specs are pretty open and the drivers are almost all there; it's the userland support that's absent). KDE 4.1 fails at it. Gnome fails at it less miserably. KDE 4.2 still fails at it. I don't know how long it will take KDE to recover, but I'm not waiting.
I don't like not having the true Linux environment at my fingertips but Cygwin does most of it passably and most of the time I'm connected to a server anyway. Yes, Putty is an ssh client, but Puttycyg is a terminal emulator, and the best one there is for Windows. And it still sucks.
Konsole running Cygwin on Windows will be a nice improvement and as close as one can get to a good platform on Windows so far.