...according to this in Deadline:
Well, I'm excited by this breaking news. Universal is bringing back what it's calling "the key screenwriter" behind the Bourne franchise to write the treatment for the fourquel, whose working title is the The Bourne Legacy. And he's also writing what studio insiders are calling the "Bourne Bible". Tony Gilroy, of course, was the key writer on The Bourne Identity, The Bourne Supremacy and The Bourne Ultimatum. Frank Marshall and Pat Crowley are back to produce alongside Captivate Entertainment which is the Robert Ludlum estate production company led by Jeffrey Weiner and Ben Smith. (The pic won't be based on the book The Bourne Legacy written by Eric Lustabader in Ludlum’s series.) Bourne 4 will have a 2012 release. No word yet on whether Matt Damon or Paul Greengrass will be back. (Matt has said he won't do Bourne 4 unless Paul does. And Paul has said he's not.) But I bet Gilroy's involvement might lure at least Damon, who'd be an idiot not to continue the best role of his life -- not to mention the best payday.
-This doesn't seem especially necessary, but there are worse projects these people could be involved in...thoughts?