Sorry, I'm a bit late on bringing this information to you since I found out a couple of days ago.
Ghibli recently announced their next feature length animated film "Karigurashi no Arrietty" which essentially translates into "Arrietty the Borrower." The film is based on Mary Norton's Carnegie Medal winning novel The Borrowers. However, unlike the book and that 1997 film with John Goodman (heh), Ghibli's film will be set in Tokyo Koganei 2010.
The film will be Produced by Hayao Miyazaki, and it will be the directing debut of Yonebayashi Hirosama. A summer 2010 release has been projected (so close!) and will have a running length of about 80 minutes. More updates as the news becomes available!