FaceBook for Scientists? (discussion opener)

Educated and employed as a scientist, you have a Facebook page.   You probably use it primarily for interactions with friends and family.  You share photos, videos.   Maybe you post silly remarks, or perhaps others tease you by posting remarks or photos that are not flattering to you.  It's your FB page, for crying out loud, not a professional journal.   So what does it have to do with your identity as a Scientist?    And if you come out of the closet as being a Chemist, Mathematician (yes, I call them Scientists too), Materials Scientist, Astronomer, Biologist...   are there any recommendations for how to achieve maximum benefit to the World and to your Career while limiting possible embarrassment vis-a-vis your hardcore Science friends?   Is this discussion significantly different from a more general discussion of Social Media vs. Career/Work for any random profession?

This is a blog entry, so much of the value (ideally!) will come from remarks added by you, the reader.
It's also just one of many entries I'll offer on this subject.   Let's start with some basic suggestions and concerns.   Then we'll build on it.

1. Audience awareness.  On FB, we tend to address remarks to widely differing groups of people. And unlike Twitter, FB allows us to carefully control the visibility of each post.
2. Forums, groups, pages:  They abound.   Many target professionals (scientists or otherwise)  of a particular area, but are open to the general public.    Learn about these resources, learn from them, and contribute your thoughts, ideas to (yes!) help make the World a Better Place -- and maybe  advance your career in the process.
3. Friending:  Policy, philosophy, ethics.   Not all users who join a discussion in forum will want to immediately accept "add as a friend" requests.   Formulate your own policy, and be prepared to communicate a "No" when necessary - politely.   If you are liberal with your  "friending" habits, do not be offended if somebody else ignores or refuses your request to be their "friend".  Remember... there's always LinkedIn.  Of course even there, many users prefer to restrict their formal "contacts". 
4. Profile:  if nothing else about your profile is public, then at least the material you list here should be screened and evaluated for acceptability and impact when people follow the link from your remark in a forum to your page.   
5. Potential:  Here's where I believe FB and Twitter truly have a great deal to offer to our profession.  Lower the "potential barrier" between those inside the ivory towers or corporate research centers and 'regular citizens'.   Be mindful of confidentiality and IP ownership issues, but engage The World in ways that make it easier for the general public - citizens, voters, and taxpayers! -- to appreciate what we do.   Attract more youngsters into careers in Science, Technology, Engineering, and Math.  Ensure their expectations are better matched to reality once they arrive.   And last but not least, consider the possibility of involving science enthusiasts of all walks of life and all portions of the planet in generating new scientific knowledge, insight into The Awesome World. 

More some other time.   I'm heading out the door for an early-morning run.  By the way:  if you've come across (or written) material similar to what I am posting, share it  with us!   The more, the merrier.