Is that so bad though? What about Broken Steel? I think if it makes a better story they should go with it.
Broken Steel was a special case, where it made better business sense to turn Fallout 3 into an open ended game than to avoid completion requirements.
I'd love to see DLC extend some of Skyrim's questlines and give them some much needed depth, but that wouldn't be likely to generate as many sales as something instantly accessible to more players.