TerreStar just announced a new partnership with AT&T Mobility which will bring a hybrid cellular/satellite phone to the U.S. next year.  The handset, the TerreStar Genus, will run the Windows Mobile operating system.

The Genus Windows Phone will:

“combine AT&T’s [3G] wireless connectivity with the ability to use an all-IP satellite network as back up throughout the United States. Using one phone number and one device, users will be able to access voice and data services in the United States, Puerto Rico, the U.S. Virgin Islands and offshore coastal waters over either the AT&T cellular network or the TerreStar satellite network.”

Features of the Genus include a 2.6-inch touchscreen, a front-facing QWERTY keyboard (Messenger style), Wi-Fi, Bluetooth and GPS.  The design is similar to the HP iPAQ 910 Business Messenger.  While the press release does not state the OS version outright, its release in Q1 of 2010 means Windows Mobile 6.5 will almost certainly be onboard at launch.

Obviously, such a phone will not appeal to a wide range of users.  The TerreStar press release states that the handset will be aimed at “government, emergency responders, enterprises and rural communities.”

No word yet on the price of the handset or how much service for the device will cost.