I think some evangelists ( Phil Haack ( now @ github), Scott Guthrie, Scott Hanselman, ...) were ahead of Nadal when changing perception about Microsoft in terms of opensource and community..

It was a bottom-top approach with Nadal as result. Ballmer couldn't understand the new wave. Just like many "old" CEO's of software companies don't understand.

I know companies who still keep programming in Access and Terminal Server, Asp forms, ... Just because their boss understands that.