Tom Felton (Draco Malfoy) and Bonnie Wright (Ginny Weasley) talked to a Belgian magazine about the Harry Potter and the Half-Blood Prince DVD release and filming Deathly Hallows, and spoke about the epilogue, which in the books takes place nineteen years later.  SnitchSeeker has the translation:

Tom Felton: ‘We still have a few months left of filming. The very last scene we’ll be filming will probably be the scene that plays 19 years later. I’m already very curious what we’ll all look like.’
Bonnie Wright: ‘I’m looking forward to return to King’s Cross. I filmed my first scene of the first Harry Potter film there 10 years ago. I hardly new what acting was about. I especially remember that I was freezing.’
Tom: ‘Together we spent over 10 years on this film set. We grew up here. It’ll be strange to say goodbye.’
Bonnie: ‘Who knows, we may have a reunion in ten years. What will become of the actors? Maybe we’ll be playing together in ‘Harry Potter, the Musical.’ (laughs)
Tom: ‘Or we’ll be skating in ‘Harry Potter on Ice.’ Although I think J.K. Rowling will luckily prevent this from happening.’

It doesn’t sound like they know much about it, other than that it will happen.  Which, I think, is the main problem.  Rowling basically wrote the epilogue and laid out each character’s fate so that no other writer would mess with her characters.  The book would’ve been just as good without it, but it worked O.K.  But in the movie?  All we’ll be doing the whole time is looking at the aging makeup and the special effects.  There’s no harm in just cutting it out.