Say that for Visual Studio or Eclipse which aren't as polished in some aspects, crash frequently, or run on platforms that crash frequently. (I'm not saying that VS or Eclipse share all 3 of those properties, and the crashing bit refers to Windows).
I've never used Xcode, but I do use Visual Studio everyday, on Windows 7. In the 5+ years I've been using Visual Studio I've been very happy with it as an IDE. Prior to 2008 there were definitely some quirks and stability issues, but as of 2010, I very rarely encounter any issues. I have lots of unix experience, and I can honestly say that Visual Studio is an excellent piece of software, and a pleasure to write software with.
As for your point about Windows crashing, I've never once seen Windows 7 blue screen or become unresponsive to the point where I had to reboot a machine. Disliking Microsoft and Windows are fine, but without some real evidence that Windows 7 is less stable than OSX, or any other OS I think this is a baseless claim.