Friends discuss each other's business amongst themselves - always have, always will. Even a little bit of bitching can be a healthy way to vent and ease any interpersonal tensions.
Depends on the issue at hand though, I guess. Some topics are private, and it's an extreme breach of trust to go yapping to a third party about them. Then again, sometimes (in a case where a friend may be endangering themselves or others) it can be acceptable. Then you have to be very careful about to whom you impart sensitive information of any kind.
Like Oscar, I really don't mind being talked about. Apart from when it's about STI's which I do not and have never carried.