between the end of the Hobbit and the start of Fellowship of The Ring.
http://www.mania.com/del-toro-talks-about-hobbit-films_article_58178.htmlDel Toro said he "traveled to New Zealand just a little while ago, and one of the main reasons for going was to sit down and talk about the second film. ‘The Hobbit’, the book, is really one self-contained film, so for the second movie we sat down and worked it out. When we did this we got really excited because this second film is not a ‘tag on’, it’s not ‘filler’, it’s an integral part of telling the story of those 50 years of history lost in the narrative. There will be certain things that we will see from the first movie but from a different point of view, but it will feel like a volume, in the 5 volumes of the entire story. It will not feel like a bridge, I’ve been hearing it called ‘a bridge film’, it’s not, it’s an integral chapter of the story, and I think we’re all on the same page."
Now, anyone else but Jackson would probably fuck up this second film since it's not based on an existing Tolkien book, but I'm pretty confident in Jackson and Del Toro's ability to pull it off. The second film will pull from Tolkien's extensive notes.