LG is expected to announce the LG Nitro HD on December 1st. The Nitro HD is the American version of the Canadian LG Optimus LTE.
According to Phandroid, an invite they received from LG did not mention any particular phone, but the file name read "LG Nitro." This lead them to believe the new phone will be announced next month, but nothing has been confirmed.
The LG Nitro HD is expected to feature the same specs as the Optimus LTE. Those specs include a 4.5-inch HD screen with 1280 x 720 resolution, a 1.5GHz dual-core processor, 1GB RAM, 4GB ROM, and an 8-megapixel camera.