Zune Phone?

I read this column that there will be no Zune phone at CES. I am not disappointed because I was not expecting a Zune phone..

It got me thinking.
Why would Microsoft launch a Zune phone and cannibalize its Windows Mobile OS? It is better off not launching the phone in this crowded, competitive market and capitalize on the network effects of third-party developers licensing Windows Mobile. Has Microsoft--which practically wrote the book on how to set up third-party ecosystems to win with Windows and Office--moves away from what has made it successful so far? I doubt that Microsoft seriously considered launching Zune phone because it will be counter to their playbook. But again, who said that strategy is always rational?
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