This likely isn't the last of Jason Bourne on the printed page. The Ian Fleming estate (operating first as Glidrose Publications, and later Ian Fleming Publications) commissioned Raymond Benson to continue the Bond series, and later settled on a strategy of appointing different authors for different books, with Anthony Horowitz recently becoming the first writer since Benson to pen more than one novel in the main series. The Ludlum Estate has followed a similar strategy with other series created by the late novelist. Numerous writers have tried their hands at Covert-One novels (a series which was handed off to other writers even in Ludlum's lifetime, and indeed created with that strategy in mind), and at least two writers have continued the adventures of Paul Janson, hero of one of Ludlum's final novels, The Janson Directive (review here). I strongly suspect we'll see another new Bourne novel sooner or later with a new name on the cover.
Meanwhile, head over to The Real Book Spy to read the entire, in-depth interview with Lustbader including his future plans.