Phil Spencer said Xbox has entered into preliminary talks with Zynga. They had spent a lot of time working out this deal, but Zynga was acquired by Take-Two.
We began discussions with a company called Zynga, which was eventually acquired by Take-Two.
Phil Spencer
This clearly shows the attractiveness of the mobile phone market for Microsoft. In fact, Zynga is a company that develops mobile applications and games like FarmVille
List of games from Zynga