Update! Paul Greengrass has confirmed reports (see below) that he has left the the fourth "Bourne" pic. "You won't find a more devoted supporter of the Bourne franchise than me", Greengrass says in a statement issued by Universal. ''I will always be grateful to have been the caretaker to Jason Bourne over the course of The Bourne Supremacy and The Bourne Ultimatum. I'm very proud of those films and feel they express everything I most passionately believe about the possibility of making quality movies in the mainstream. My decision to not return a third time as director is simply about feeling the call for a different challenge. There's been no disagreement with Universal Pictures. The opportunity to work with the Bourne family again is a difficult thing to pass up, but we have discussed this together and they have been incredibly understanding and supportive. I've been lucky enough to have made four films for Universal, and our relationship continues. Jason Bourne existed before me and will continue, and I hope to remain involved in some capacity as the series moves on."

Here's the original story :

The fourth ''Bourne'' film has lost it’s director - well, for the moment.

Yep, Paul Greengrass, director of “The Bourne Supremacy” and “The Bourne Ultimatum,” has apparently exited his post as helmer of the Matt Damon-led sequel. The Playlist says nobody was happy with George Nolfi’s script, but Greengrass wasn't happy he was never consulted before the studio hired Josh Zetumer to pen another.

The official word, back in August, was that Universal were in a hurry to get going on "Bourne 4", but Nolfi was knee-deep in his film "The Adjustment Bureau" (starring Damon) so they hired Zetumer, and hoped Nolfi might return to the project later on so both could, I assume, combine scripts?

Personally, I think this will all turn out OK. Greengrass is known for walking off, then walking back on, films, but more so I can’t see Matt Damon not being able to convince his friend (and the second reason – the first being money – he agreed to do a third sequel to “The Bourne Identity”) back from the bar.