Another entry to this post: insurrbution.blogspot.com/2012/09/new-editions-for-wheel-of-time.html , Book 9 info has now been added.
The 'next' book in the trade paperback re-release to receive info, is Book 9, Winter's Heart.
It will be released March 25 2014, and the book info so you can look it up on Amazon, etc for your ordering pleasure is:
I have seen some of the trade editions of other books in the series, and they are quite nice, as far as book quality goes. Much better than a squashed mass market paperback. If only these had existed when I started buying the series way back....
The next title in the series to receive release info (date, ISBN) is Crossroads of Twilight... I'll keep you posted.