If this two year plan is real, I wonder if the intent is to provide a small but constant stream of new content until the next full game. I shudder at the thought of two more years of Gamebyro crazyness, but the idea of constant content isn't too bad.
People have already lost interest in New Vegas for varying reasons, Whether it be gameplay, combat, or in some cases because of Steam...and now this deal with Microshaft to give exclusivity to the XBOX and leaving two thirds of your base out in the cold will turn even more customers away. This to me does not sound like a very good business decision.
Like I said, In two years I will be playing Skyrim and thinking about Fallout 4, not New Vegas and I suspect that most of the remaining folks that are now still playing New Vegas will be doing the same. I also suspect that after 11-11-11 the New Vegas forums will be about as active as the Fallout 3 forums are now. That doesn't bode well for the remaining DLC...especially if there really is a two year plan of releasing them.
The future doesn't look very bright for New Vegas. It's ashame because it has alot of potential to be really great, but one bad decision after another has svcked some of the life out of it.