I used to disagree with this assessment, but I have been using Linux and Windows these last few years (and trying to make them work and look as similar as possible), and nowadays I tend to agree. The worst thing I can say about Windows is that it lacks a Unix commandline and package manager, but on any decently powerful, modern machine, you can use (VirtualBox+Ubuntu|ElementaryOS)|Cygwin to remedy that for free.

The iPhone is still my favorite phone. But I wouldn't take a Mac OS X box over a Linux box for professional development. That said, my opinion on these things changes constantly, so who knows how I'll feel in a year.