Very few in L.A. actually say "on your left" when approaching someone you are going to pass. In Sherman Oaks, I tend to get "thank you for letting us know," when I do it.
Last spring I was driving in Valencia behind a female bicyclist who ran a red light talking on her cell phone. Speaking of cell phones, while running the Run Hit Wonder 5K in September, I was passed by a runner gabbing on her cell phone about nothing-too-exciting. Sad thing is, she was the one passing me.