
With facebook, I only "friend" those people that I actually know and with which I am maintaining a relationship. I like the control of this in Facebook while enjoying the openness of Twitter for other reasons.
Theresa, I liked how you summarized your update strategy and am trying to adopt that approach.
I think Bill Gates leaving Facebook due to having "too many friends" was not so much due to him being a dismissive user as people will joke, but really because he did not create a controlled space for himself where he was comfortable (Facebook and Twitter were used in the same way) - I actually wrote about that on my blog.
My messages on FB are a lot more geared towards what I'm doing, and my tweets are more about what has caught my attention. People use different approaches, but as long as they're used consistently, it seems to work.
I think this is a very important topic you bring up because it will allow for more people to start feeling comfortable using different spaces knowing what boundaries they set for themselves. I guess at the end of the day, it's back to the whole target audience idea - answering the question: Who cares? For my baby pictures, I'll post them for my family and close friends, because they will! For those I am following regarding health care modernization on Twitter... probably not...