The Xbox thing actually emphasizes the principle
Yes, I HAVE an Xbox, the same one we had to send back for the heat-sink problem. The point there, however, was that it wasn't the hardware that made it popular, it was Microsoft's deal with EA (Halo, duh) that made that product a success. Again, it was all about the APPS! Without those, Xbox would have been a huge money waster - it was way behind both the Nintendo Wii and the Playstation in the market, but - yet again - nobody buys gaming boxes (and you can insert PC's, servers, etc. here) for the platform, they buy them for the GAMES/APPS.
Microsoft needs to find Halo for Windows Phone 7 to drive up its market share. Until it does that, my crystal ball says that the market just isn't going to care much. That doesn't preclude Microsoft from flooding the market with $1 billion worth of products, gimmicks, and advertising (which IMHO would be a good idea for them). My contention was that the carriers aren't going to shill for Microsoft when there are well-established players already with a commanding lead.