I believe Linux would benefit greatly from more and better Windows ports of popular OSS applications that are common on Linux desktops. If you get people using the software the time will come when switching the OS they run on is an afterthought. Plus you gain the possible contributions of millions of Windows users who have no interest in Linux but may very well want to run good OSS software. I'm not sure this is a viable strategy with GTK or QT as the Windows implementations are subpar at best. Mono is probably the way to go if you're an OSS developer interested in creating an app for everyone to use -- not just the people who happen to accept your personal choice of operating system. Isn't that (basically) the bitch that most Linux fans have about Windows-only software? Seems silly to advocate the same solution replacing win32 with GTK or QT. While they may technically exist for Windows they are not adequate -- probably comparable to running win32 apps on Linux via WINE.