JJ Abrams seems to enjoy being an Executive Producer as he has signed on for a third film with Paramount. The film is called Wunderkind written by Patrick Aison. It is set in the 1970s as it follows a CIA and Mossad Nazi hunters who are forced to work together. In the last few weeks Abrams has signed on for God Particle and an untitled spec script. Abrams is currently working on completing the Star Trek sequel but this is unlikely to interfere with that.
Keep in mind that the Executive Producer is kind of like the CEO of a film. His job isn't the day to day decisions. Those are delegated to those with "Producer" credits that are not stars on the films. His main role is to interface with the studio, bring legitimacy to a product (think "from Steven Spielberg..." type lines you see in movie ads), approve the director (and sometimes the cast) while providing comments and ideas on the script with the occasional set visit when production starts. It’s a low time commitment but high paying role as often the executive producer gets a piece of the profits. Really if your goal is to make as much money as possible, this is what you eventually want to devote most of your time to (again see Steven Spielberg) as get credit for making films while not involved in all the time consuming minutiae that is involved in getting a film made.