Windows USB Update for Windows Phone 7 popping up

Here's a bit of a mystery.

There is a Windows Phone 7 update available for your Windows operating system. It won't show up on your update list unless you have Zune running and your Windows Phone connected.

Listed as Microsoft-Other hardware-Windows Phone 7, the 4.2mb update apparently deals with your USB connection and recognizes the Windows Phone device by name. Gone is the generic "Windows Phone device" identity whenever you connect your Windows Phone.

As to the "why", your guess is as good as ours. Could it allow Microsoft to open up the device specific apps to the Zune Desktop? Could it be a sign that the Mango's release is close at hand?  Or could it simply be someone at Microsoft getting tired of seeing a generic description of your Windows Phone?

Thanks goes out to Jarrod and everyone else who tipped us on this!