Hey, the 90's called, they want their cynical, short-sighted view of open software back. If you don't understand how open software is important, then you have been living with your eyes closed. As far as everyday usability, perhaps you need to define exactly what usability is. I, for one, think that instant availability of a monstrous volume of free software is a huge usability bonus. Want to talk about an eco-system? Try perusing the Ubuntu or Debian apt repositories. It is also nice to have a file-system that actually makes sense and is completely accessible. Security is a pretty important aspect of usability, and no one can seriously argue that M$ has ever been able to deliver superior security to its users. It's also nice to have regular-rolling updates to your operating system along with easy access to news and feature updates. Of course there's the plethora of free "substitute software" for pretty much every single software product that Microsoft sells. There's also amazing FREE, OPEN virtualization solutions if you just really have to have a Non-free OS installed. Oh, and there's the whole universal deployability thing...

WP7 won't flourish, even with backing from a major manufacturer. There is already a tightly closed mobile OS in the market place, and the competition has an established and loyal user-base. Microsoft's attempt to get a serious slice of the mobile market is about as feeble as Apple trying to gain a significant share of the desktop market. The other guy already has what you have plus customers.