Christopher Carfi pointed me to this essay by Chris Brogan titled Cavemen at the Fire that captures the essence of the “why” of blogging for so many of us:

But the truth is, I'm getting value. I get value in talking with you. I've met so many engaging people, and every time one of you risks delurking and sending me an email, I meet a new friend….  I feel that every day I post something new is another micro resume. I'm telling people out there what I stand for, how I think, what matters most to me. Some days, that's probably not going to land me a job. Other days, it's something that people might relate to.