right, an engine is what makes a video game what it is.
Fallout 3 is a bad game because they took the universe and distorted it. it's exactly what happened when Fallout Tactics got made. both games are inconsistent. New Vegas, on the other hand, stayed true to the original BIS games. not only in lore, but in gameplay and style.
so, excuse me for being skeptical, but I don't see how a group of people that never worked on any of the original games, could make a good sequel/spin-off. they don't understand how half of it works and why it clicks with the player. Fallout 3 wasn't all bad, but they couldn't deliver on the most important part. and if Bethesda couldn't, Masthead won't either
Masthead will make a generic post-apocalyptic MMO, with the name "Fallout" stamped on it. of course there is still a chance their game will turn out decent, but Interplay should've buried that project long ago. Masthead aren't the ones to blame of course, they're the prisoners (or "hostages", not sure what's the English variant) of circumstances in this story.