Interplay was supposed to have engaged in full-scale development on the Fallout MMO by last Thursday, April 9th and this apparently also included raising the funds for the game as well. We know some sort of movement had been made, but apparently it was too little, too late. That's a tall order for any company to pursue, especially one with a very sordid financial history.
Should Bethesda move forward with this and win, we can only assume the company will pursue its own Fallout MMO. Then again, who's to say they haven't been planning for such an occurrence all along? Bethesda was contacted for comment, but declined to do so.