The One Piece series of films had been coming out annually every year since the production of the anime series started. Fans were excited when they heard that the series creator, Eiichiro Oda, was going to personally oversee the production of the tenth film. One Piece Film: Strong World was the end result, and it was actually tied into the main canon of the manga. Well, it seems that Oda wasn't satisfied with doing this once.
It was on December 17th 2011 that a both VIZ Media and Hisashi Sasaki (deputy director for theShueisha's Shōnen Manga group) announced via Twitter that Oda would once more be the executive producer for the soon to come One Piece movie. The original green light announcement for the project was shown in Japan during the TV airing of Strong World back in November.
The title of the One Piece Movie 12 has not been given, and the only release date given is sometime in December 2012. The premiere will be held at Tokyo's Roppongi Hills' new One Piece art exhibit. What's known about this production is that it will be set in the post time-skip New World Era of One Piece. Given the schedule of where the anime is currently at. It's a safe bet to say the events will happen after the Straw Hats leave Fish-Man Island.
The questions that this leaves me with. Is Oda going once again somehow work in characters from the movie into the manga series the same way he did with the antagonist Shiki? Also, will FUNimation ever even license Strong World for the U.S. market? To date, they've only released the eight movie.
Source: ANN HERE