The idea of a Windows phone sounds about as bad as a Microsoft Vista computer. But a vastly-improved Windows 7 redeemed Microsoft's PC operating system business. Now the company hopes the same restorative medicine can work in mobile phones. You can look for a blitz of Windows Phone 7 devices arriving ahead of the holidays. And here's a hunch, with the AT&T ( T) and Apple exclusive partnership coming to an end, Microsoft could play a big part in filling the iPhone void.