User blog comment:Kacj321/Entire Tamriel Landmass built into Skyrim/@comment-4436526-20111124010331/@comment-3144388-20111124030930

Bethesda has no hand in any Fallout MMO. Interplay is fighting a legal battle with Beth over rights to produce a FO:OL. And the graphics would have to be toned down to that level to handle the traffic an MMO receives.