Wall Street Journal is reporting today that AT&T will supposedly be the exclusively carrier for Windows Phone 7 at its launch -- which is currently unknown. Microsoft is holding a mystery press event on October 11th, and that will be the likely date for Microsoft to not only announce the public availability of Windows Phone 7, but also showcase new smartphones with the OS preloaded onto them. In fact, WSJ says that Microsoft will be specifically unveiling three new handsets on that date that will be available on AT&T during the week of November 8th.

Microsoft knows they have to act quick in launching Windows Phone 7 and they must do so successfully. It is crucial for Microsoft to get this right in order for them to still be taken seriously in the mobile arena. Plus, with the failure of the Kin just a few months ago, another embarassment is not an option.