From the perspective of the major audience of Dr who, season 6/7 have been extremely heavy on the story arcs and people are getting sick of it. e.g. "River's story has gone on for too long".
I really can't find the story arc in seasons 1 - 4... What was it?
http://en.wikipedia.org/wiki/Story_arcs_in_Doctor_Who
There you go poppit.
Also, in response to River Song, I like her. I think she's interesting and fun
.
I can't speak for the whole audience when I say I like the longer story lines, but I really do.
As I mentioned before, I love solving it along side the TARDIS team and cluing it all together as more information is released each week. I like all the speculation and wild mass guessing that goes on
I like being able to sit down, re-watching episodes and picking up more information, or seeing how small seemingly unimportant details were actually hints.
I like the story arcs because they are generally deeper and leave a lot more to think about. If each episode/2 episodes were resolved, there would be a lot less to speculate and discuss during the breaks. Essentially, we wouldn't be talking about what may happen in season 7 right now if we didn't have story arcs, mysteries or clues to go off.
tl;dr I fangirl over Moffat.