Hello! Long time lurker... first time poster (I think).
I'm usually very pessimistic and for a long time figured that the third Hobbit wave would be the last in the LoTR and Hobbit lines (due to obvious poor sales). However I was checking out "The Lonely Mountain" set and noticed something strange. I don't remember it being discussed before... so I thought I'd bring it up.
http://imgur.com/jNJmVgG
That little "hole" brick on the side (no idea what it's called) hints that there might be another Erebor set to connect to "The Lonely Mountain" set.
I wouldn't be surprised if Lego ended the Hobbit line with a UCS Erebor or perhaps even when the final extended edition comes out.