I work in a research lab that has federal funding from multiple sources including the NSF, NIH, and NEH. We tell them upfront that our development and implementation will be in Windows only and we have had no problem securing funding.
I own a Macbook Pro, an iPad, and an iPhone and they are all super neato. When I want to get work done, I work in Windows 7.
Apple is a cult and the funny thing about hardcore Apple users is that they all think Apple is friendly to the open-source community (though they don't even know what open source means). Their argument usually goes something along the lines of "But...OSX is built upon linux or something," as they peer at me through their black rimmed glasses and twirl their indie mullets.