It looks like despite Microsoft releasing a new-from-the-ground-up Mobile Platform, they've already conceded that they will be unable to compete in the mobile space unless they threaten, bully and sue. And so they have.
Microsoft today announced and launched a patent infringement suit against Motorola (and thusly, Android) for patent infringements on it's Android line of phones. While Motorola is specifically named, make no mistake, this threatens the entire Android ecosystem much like Apple's suit against HTC.
You can read their justification at the Microsoft Technet Blog or you can view the full Press Release.