From Martin's latest not-blog entry:

"Just musing aloud here, so don't anyone get all hysterical... but depending on how long the book comes out, moving some of these finished chapters into WINDS OF WINTER may make sense. Structurally you could make a good case for making DANCE a perfect parallel to FEAST; different cast of characters, but exactly the same time frame, so both books end on the same approximate date. Then WINDS could pick up the action for both sets of characters the following day.

That's not the way I have been doing it, however. As written, I've covered the FEAST time frame in the first 800 pages (manuscript pages, the printed book pages will be different) of DANCE. Everything that follows is post-FEAST, so that's where some of the cast from the last book start popping up again. Not the most elegant structure, I admit... but given how late this one is, I wanted to resolve at least a few of the cliffhangers from FEAST... (if only to set up the new cliffhangers). So..."

For what little it's worth, I thought I should go on record to say that the idea of splitting based on chronology would be a huge mistake. To say nothing of the fact that circa 800 manuscript pages would produce a frustratingly short volume after a five-year wait, and presumably the shortest one in the series to date, leaving Dany's plotline before her potential suitors arrive would mean that we can probably expect minimal plot progress in her arc, which would put off a lot of readers. I think Martin's best course might be to compromise and cut selectively from the Feast cast, leaving Dany's suitors in Dance but leaving Cersei, Brienne, and some of the others for Winds.

Any thoughts?