There's no way in hell Chewbacca will NOT be appearing in the sequel trilogy, as I and many others have said before. However I feel like all of the events that took place over the past few years (death of Jacen and Mara Jade, etc) have been the authors way of cleaning slate for the imminent release of the sequel trilogy. If they are gonna make a last minute retcon/change in an attempt to keep the whole post ROTJ EU alive, its gonna have to be Chewie's death. which is why I fully expect them to have him show up alive somewhere with some sort of haphazard explanation. Perhaps in Crucible, since its the "final" novel in the timeline to include the Big Three as main characters?