If you hire Vin Diesel, you might as well just get comfortable with the idea that he's going to share things on his Facebook page, and he's going to do it on his timetable. He likes to share. He shares a lot. And at this point, he's worth quoting as a source because whether his information is "officially" confirmed or not, it is eventually revealed as correct.
Good example: how long now has Vin been teasing the idea that he's contributing the voice of Groot? And now, Marvel has officially confirmed that he'll be playing the character, contributing some motion capture as well. The other big project he's got brewing, made only bigger by the unfortunate recent accidental death of co-star Paul Walker, is "Fast and Furious 7," and there has been much conversation for the last few weeks about the film's release date.
Originally set for July 11, 2014, the film shut down production so that everyone involved could deal with the impact of Walker's death. These weren't just films that paid lip service to the notion of family, but were actually made by a group of tight-knit people who had gone through so much together, and it must be incredibly difficult for them to have conversations about how to proceed finishing the movie.