I'm not sure the folks in Visual Studio are representative of all of MS though. Being a business unit where our customers are developers, the PMs have to also be developers. I'd be surprised to find PMs in WP or Xbox writing as much code as the VS PMs do.
That would never have flown in a Sinofsky organization. The marching orders were PM's define the what and dev's define the how (and test makes sure it works), and it was driven down to everyone in the trenches constantly.