Just want to second what Rachel has said: right now if you google Everett, WA and Chiropractic or Chiropractor, you get me in the top 5-6 on the "organic side" (You start talking like that when you hang out with Israel Rothman (www.rothmanmarketing.com) for very long.) And that is without even doing any blogging since October.
Blogging seems to be just one of the many ways of adding to your web presence - these posts also help - and just being in Biznik seems to be very big.
So for me blogging serves the function of increasing SEO (Search Engine Optimization - I've only known what this acronym meant since talking with, again, Israel at the last Everett Happy Hour meeting).
It turns out to also be very true that who you really are comes through in your blogging and that attracts people who can connect with that: and it filters out others who do not connect with it.
Blogging is also a way to archive discussions which you can then direct patients to who need to understand some concept that you have repeated out loud 5 million times: now you can just say "read about it on my blog."
In theory a blog is also a place for dialog and feedback, but that assumes you are a power blogger like the Biznik blogmasters. Like a popularity contest it takes certain types - and one part of being the type is to put in all the time necessary to juice up your blog with power features, trackbacks, tags blah blah blah.
Blogging takes a certain amount of time and effort, but I think it is a good investment given all the other options. Like anything else you get out of it what you put into it. And if you're considering it I recommend Rachel and Dominic's class. It is bound to be a good use of your time. I couldn't get to the last one, though I tried. Dennis