The elephant in the room here is cost. I work in various flavors of Visual Studio every day, and it is a nice IDE, but if I was bootstrapping a company, I'm not sure I'd want to shell out the money for an MSDN subscription[1]. I get the impression from the post that the toolset was already in place (paid for).

[1] I haven't looked at subscription options recently, so perhaps there is a start-up friendly level these day?