Today technology is commonplace and more widely distributed. I would place danah boyd in the same category as those you have mentioned because of the fact that the computer/tech/internet worlds are so much larger than it was in the 80s. She is a leading intellectual when it comes to social networking and I hope she has some influence at Microsoft in a positive direction. Because of her large amount of knowledge in the technology space as it applies to its social impact, this is indeed a key hire for Microsoft as they struggle to make heads or tails of how companies like Google and Facebook have had such a huge following.
I'm not saying that she doesn't have value, but calling her a "key hire" at Microsoft is a pretty big stretch. "PR coup" is a lot closer to the truth....
Please remember that Microsoft has been flailing from the beginning when it came to accepting the internet. They need all of the intelligence they can get in order to be ahead of the curve in relation to social impact.