Comicpalooza is on May 23-26. It was recently confirmed that Episode VII will start filming in May of this year. Mayhew doesn't film projects that often, so it's possible that he could be back to play Chewbacca. Of course this is nowhere near a confirmation and should only be treated as a rumor for now. The film will be directed by JJ Abrams from script he wrote with Lawrence Kasdan. It will be released on December 18, 2015.