Hi G.,
I want to jump on the support for San Ramon Valley Primary Care (http://www.srvpc.com/)
My daughter has seen Dr Obrinsky since she was born, and we couldn't be happier. I chose them because they had privileges at John Muir, where I delivered, and my OB recommended the group. Dr Obrinsky was on duty that week and was just awesome with my daughter. (He got bonus points for changing a dirty diaper) He's great with my daughter, and has been wonderful with all my new mom questions. What impresses me with Dr Obrinsky is his focus on the development of my daughter, and me as a mom. I never feel rushed, he does the check up, talks about things we should focus on until our next visit (whether it was tummy time, introducing rice cereal, etc..), and then allows me to ask questions. He doesn't end the visit until I am done. This is huge for me. I don't want to feel rushed with my daughter, and I want to talk to someone who really knows what he's talking about. (helps that he's a father of three, so it comes with personal experience as well)
As you have seen from other postings, I think all pediatricians with this group are great. We saw Dr Trotter once, and he's excellent as well. They have their own advice nurse, who is extremely helpful.
The group has "meet and greet" nights, so you can interview the pediatricians before you choose. We had planned to go, but it was the same night I went into labor!
Check out their website and read about the doctors. I was impressed with all the doctors education as well as their continued work as professors at UCSF medical school. My husband had a pretty significant surgery through UCSF, where I learned just how impressive their medical program is. I now only choose doctors with involvement with UCSF. Outside of their education, I think you'll find that San Ramon Valley Primary Care is such a positive environment.
Congratulation, and all the best to you and your son!