I have had two sponsors and fired them both. I love AA and just finished a noon meeting, but what I have learned in my almost 6 years of going to meetings is that while we say "What we say here stays here", well, it's not always true. There is no liability or actual confidentiality in AA. So for myself if I want something private I don't discuss it. That bing said, in our group it is normal to have sponsors in the meetings with their sponsee's.
I will never do any step work with a sponsor again, but I do step work in a way with my shrink. If she ever talks about me to anyone she can be in big trouble due to patient doctor confidentiality.