And then there were three. AT&T's lonesome LTE duo -- the Samsung GS II Skyrocket and HTC Vivid -- just gained a new member with the recent launch of LG's Nitro HD. You may recognize this particular handset from its former life as the Optimus LTE, except here the phone's been rebranded with a moniker that more astutely conveys its blazing 4G purpose. There may be tough times ahead for the handset, considering the current crop of high-end devices h
