I don't have a problem with oversharing or TMI (too much information). People have the right to share whatever they want. If you don't want to share, you don't have to. If you don't want to hear that much information, then you can choose friends who share less.
I'm not into social boundaries. I respect the boundaries that people set for themselves, and I have my own boundaries, but I don't accept social boundaries as a given. I choose not to think about work or school outside of work or school, but I also choose to share whatever I want about my personal life with my classmates and co-workers. In fact, I wish I had the guts to share more personal info at job interviews because I want to make sure that I'll be accepted if I do end up working there. When people didn't accept me for who I was in college, my mom said that I shouldn't share so much about myself. I'm not willing to do that. I like to talk about everything, and if I don't have my parents or my boyfriend or a close friend to do that with, I will share with everyone around me. Additionally, I'm not interested in being friends with someone if I can't share things with them.
The only time I ever question whether or not someone should share something with me is if the information involves someone else. For example: if someone starts talking to me about their sex life, I feel a little uncomfortable because I wonder if their partner wants me to know. But if I knew that their partner didn't care, then it wouldn't bother me. I don't think that any personal topics are off-limits unless they involve information that is not yours to share or they hurt the person you're talking to.
If I were hiring someone for a job or accepting someone into something, I assume that I'm getting the whole person, baggage and all. I come with baggage, and I assume that other people do as well. If someone chooses to compartmentalize their life or not share everything about themself, that's their choice, but I would never assume that I'm only accepting part of someone. People are a package deal.