i dual boot linux (ubuntu) and XP, linux for work. aside from the fact the lots of work related stuff can't be done on linux, here's my list of specific problems:
- OpenOffice graphics problem; disappearing menu
- Flash problems (well, blame it on adobe)
- dual screen display problems (workaround available)
- emacs version problem (substantial problem, since i use emacs for everything)
- theme switching problems (crashes computer)
- graphics acceleration optimization problem (finding appropriate libraries, very problematic)
the list goes on and on and on. most problems are solvable, but takes way too much time, and sometimes the solution is only a workaround. ubuntu is definitely easier than red hat (which i used to use), but still some ways off. linux is, after all these years, still nowhere near as useable as Windows. you get what you pay for. there's no free lunch--if you use linux, be prepared to spend lots of time debugging stuff, and time is money.
there are nice features... like multiple desktops, a terminal where you can issue commands, but securities issues aside (which i don't run into much) the advantages are by and large random.
ironically, many of my colleagues have switched to Mac. many windows programs they need have been ported to Mac, and the fact that Mac is a Unix system seems to make some things easier to do (like this terminal program). it's more expensive, but again, you get what you pay for.
there's stuff like VMware though (right? i don't use it... yet), so definitely more and more people will "switch" to linux and use Windows as is necessary.
the Wii is an epidemic.