Scott Diener has been the Vice President and News Director of the KCBS-KCAL duopoly stations since January 2010. According to the stations, he just announced that he is leaving to pursue other opportunities. I don't know any backstory, but there's a statement from Steve Mauldin, the duopoly's president and general manager.
Scott has been a terrific news director and, on a personal note, a good friend during our nine years together in Dallas and Los Angeles. He should be proud of what he has accomplished here in Los Angeles during his time at CBS 2 and KCAL 9. We wish him the very best as he moves on to his next adventure and look forward to building on the success that he helped create.
Diener came with Maudlin from Dallas in 2010. Diener hasn't tweeted since June 17. His station website bio points out that Diener "is responsible for overseeing the largest local television news operation in Southern California – an organization that produces more than 70 hours of local newscasts each week."