In JK Rowling's only British television interview for Harry Potter and the Half-Blood Prince with 14 year-old Owen Jones, Rowling discusses the dread she will have in finishing the Harry Potter series and how excited she will be about taking on an assumed name for additional books.
You can read about the interview here:
On finishing the Harry Potter series:
I am dreading it in some ways. I do love writing the books and it is going to be a shock, a profound shock to me. Even though I have known it is coming for the past 15 years, I have known that the series would end, I think it will still be a shock.
When asked about book 7:
I have already done some work on it and I am still doing little bits and pieces, but realistically I have still got a very young baby, so I think probably next year I will do the proper writing of book seven.
Thanks to everyone who let us know that Rowling also mentioned that Lupin will not be killed by Wormtail.