It's not the end...

of the Harry Potter world. JKR has said in an interview that she is preparing an encyclopedia of facts on the characters of her books in order to utilise all her copious notes. In this article she says
“I've said before that Dean Thomas had a much more interesting history than ever appeared in the books”
When the book is released, we'll be able to learn all about that history. :D

(This is the last of the series, I promise!)