"Peter Jackson is directing the next one, I'm producing. We have a script and we're going to start performance capture probably at the end of this year. Don't hold me to it, but we're hoping the film will come out around Christmas-time in 2015. We know which books we're making, we can't share that now but we're combining two books which were always intended to be combined by Hergé."
This falls in line with what Peter Jackson said back in December, but many were speculating how the filmmaker would find the time to direct this motion-capture/animated adventure, with The Hobbit: The Desolation of Smaug slated for release this December, and The Hobbit: There and Back Again hitting theaters next holiday season.
While it hasn't been confirmed which two books will be combined, many believe it will be Prisoners of the Sun and Seven Crystal Balls. Steven Spielberg did hint that The Blue Lotus will likely be adapted for the Third Tintin Film.