No. The series is complete.

: There are rumours around that there is a considerable quantity
: of unpublished information on Tolkien's langauges (grammar,
: dictionaries and the like) stored in the Bodleian library.

There IS a great deal of unpublished linguistic material.

: Is it true that the Tolkien Trust is refusing to allow this to
: be published, and even refusing to allow scholars to see these
: documents? If so, why?

Last I heard (from what I consider to be two reliable sources), this is completely untrue. However, the people who have been given charge of the linguistic material appear to be publishing it only through Vinyar Tengwar, which I think is a shame. But they may not have been able to find a publisher for a book.

: There are also rumours that there is a further batch of Father
: Christmas letters around somewhere. Apparently, Father
: Christmas used to write once in the summer and once in the
: winter, yet only the winter letters are published. Anybody know
: more?

This is news to me.

: I have also heard rumours that a book is in preparation on the
: history and creation of *The Hobbit*. This is not being edited
: by Christopher but by somebody else. Can anybody say who is
: doing it, and when this book is likely to be published?

Taum Santoski started working on a book whose pre-publication was said to be MR. BAGGINS, but he died and the project was taken over by John Rateliff, who has not yet produced it.

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