http://www.animenewsnetwork.com/interview/2007-03-18/fuyumi-ono-author-of-the-twelve-kingdoms

I haven't read all the way through it yet, and I'm still shaking with excitement. Here's a teaser that should make waves, though:

The last novel, so far, was released in 2001. Do you plan to revisit the world of The Twelve Kingdoms and write more stories for it?

Yes, I do.

I'll do an update later once I'm able to digest it all!

Courtesy of a tip from 12K-TP The Twelve Kingdoms Fansite forums!