This is as close as we have seen to an official announcement about Lionsgate greenlighting the second Hunger Games movie, Catching Fire. It’s from the Lionsgate Publicity site and says that Catching Fire will be released on November 22, 2013.
Of course, a lot can happen between now and then and this is likely contingent upon how Hunger Games does in March. But if Lionsgate is expecting the blockbuster series that everyone else is talking about, it makes sense that they would get this on the calendar now. Coincidentally (?), this is the same weekend as some of the Twilight movies have be released in other years, including Breaking Dawn this year.