Josh makes a note about why the MS Dev Team is sharing information and the concept behind it is a great one. One of the nice things about open source projects is the overall transparency of how the project is going - well, it's possible to have that same transparency in non-open source projects which is precisely what they're doing here.
It's also a concept that I'm reading about in Guy Kawasaki's Art of the Start. When you're a start-up and coming out with a new idea, you need to keep it hush-hush until you're ready to come out with it (in fact, RIM did this with their Blackberry device) - but when you're a larger company and you need people to support you, you need to open it up and share it with as many people as possible to get them behind you.
I wish a few companies I work for would do the same with their dev teams. There's nothing worse than having to speak to customers about what the Development team is doing when getting information from them is like pulling teeth.
MS is the whipping boy for so many different groups right now - it's nice to see that they are openly canvassing for greater transparency in their new development.
Giuliani and a Glimpse of Transparency to Come