That an appointment has already been made was denied by the official diocesan spokesman, but either way everyone knows a new bishop is coming sooner or later. The cardinal reaches retirement age (=75) in 2011. In fact, Cardinal Mahony himself has announced on his own blog that this will be "my final full year as the Archbishop of Los Angeles". Thus whether or not an appointment has already been made, everyone knows a new bishop will be taking over in the next year or so. If, as the rumors suggest, a coadjutor bishop is going to be appointed, it would seem that it would happen soon.
Predictably, there is tremendous speculation about who the successor to Cardinal Mahony might be. A number of bloggers have picked up on the story, including Deacon Greg Kandra (Deacon's Bench) and Gene Maddaus at LA Weekly. Rumors are flying left and right.
To those outside the Catholic Church this might seem a little bizarre. But really, this kind of speculation is ancient. In fact, this kind of intrigue is just about as old as Christianity itself.