Glad to hear you are overall doing well.
It also sounds like you are making changes in your technique to make recurrent problems less likely - more "pronation", with your chest aimed up at the ball, and with less attempt to reach tall and impinge your shoulder.
Your serve technique doing more harm than good? http://www.youtube.com/watch?v=GgdXawklcZk
Angle of Racquet on Serve
Are you following Jim Mclellan's advice - "You've got to drop the left shoulder."
Preventing Rotator Cuff Injury http://www.youtube.com/watch?v=lTRvxaBMh8s
[I remember last spring when you were undergoing surgery - just for a clean out, not major shoulder surgery.
I remember wishing good luck for a happy, healthy 2013 without shoulder issues. I wasn't trying to be a wise guy. I really think patients and surgeons are not really prepared for the long healing phase for a motion as violent as serving a tennis ball - it takes a long time.
Maybe a little early for New Year's greetings, but again I'll wish you best wishes for a happy, healthy 2013!]