I don't know. I work in a very professional setting/organisation and of course I don't share my deepest secrets but I would honestly feel pretty odd if I couldn't share a bit of myself with people I get to spend such a huge amount of time with.
Colleagues bring their kids/spouses in the office all the time etc. Most, incl me will have pics of their kids on the desk. I get the best birthday presents because they know my likes/dislikes - that couldn't be achieved if everything is guarded. It also helps with networking. I recently mentioned something about my background in a convo and a chief exec who was in a meeting I was attending - heard it and a very positive opportunity came out of that.
Whatever someone's sexual orientation in the office, I swear no-one bats an eyelid. And it's a large org.