Six TOS, by my count: Allegiance in Exile (David R. George III, Feb.) Devil's Bargain (Tony Daniel, March) The Weight of Worlds (Greg Cox, April) The Folded World (Jeff Mariotte, May) The Shocks of Adversity (William Leisner, June) From History's Shadow (Dayton Ward, August) ...And that's not counting the novelization of Star Trek Into Darkness (Alan Dean Foster, presumably in May).
and don't forget Star Trek: The Next Generation: The Stuff of Dreams by James Swallow. It's a novella length ebook exclusive. Of course, the title is allegedly a place-holder so it could change and it may not actually be a TNG title when it gets closer to publication...
The S&S catalogue entry for David R George's novel now says that 'The Fall' is "part of a five-book story arc that takes place over a sixty-day period". https://catalog.simonandschuster.com/TitleDetails/TitleDetails.aspx?cid=1304&pn=&isbn=9781476722177
This is the full text which appears on the S&S website.. which makes me want it NOW: The Federation is rocked to its core as the Typhon Pact is suspected of being behind a barbarous act that shatters the fragile peace of the Alpha Quadrant. An original Star Trek novel, this is part of a five-book story arc that takes place over a sixty-day period, but it’s not necessary to read each novel in order to follow the storyline, which involves all aspects of The Next Generation and Deep Space Nine universes.
Well, Book 1 is the September title, and the publication year runs from February to January. So there are four titles that haven't yet been announced as part of the 2013 schedule, the October through January books. And there are four parts left in The Fall. And in recent years we've had plenty of multi-book series released back-to-back, and few that have been released more gradually. So I think it's safe to assume that The Fall will occupy the final five months of the 2013 release year.