My topic has my opinion on it feel free to reply http://www.gamesas.com/topic/1390879-next-dlcexpansion-for-skyrim-ideas/

Not bugs it seems

IMO obsidion destroyed new vegas....the story was great but i never really finished the game due to the bugs, glitches, and crashes...worst RPG ive played.....skyrim is buggey but NV was a train wreck

The thing about FO4 is that they're using the creation kit a skyrims engines to make it, so it won't take as long in that aspect. But yea I'd say they have different teams working on hearth fire and FO4. I hope someone was right when they said they're not wasting time on TESO. Not hating on it, but I don't want them spending they're resources on a game, that despite its name, is incredibly different from anything they've done.