A friend recently asked the question to her fans - why do you blog?
I answered her in a comment that seemed to go on and on - so will re-post here.
I had a web page for a few years, mostly to publish my graffiti photos. Other than adding pics from time to time, it was fairly static.
I read about about blogging (online of course), read a few, and liked the concept. After trying a few free ones, I settled on using Typepad.
I like to read other people's blogs as yet another way to experience the world and some of the people in it. I have an inquisitive mind and like to explore and learn. I have some regulars I check thru RSS (via Bloglines) and often wander thru links on them down various paths.
And I have a blog myself because I like to get my ideas and pictures out there, to expand the world a tiny bit for someone else. And maybe get a comment here and there, maybe even make some friends. I find that even without feedback, just collecting my thoughts on a topic and doing a bit or research is a worthwhile exercise for myself and helps me develop myself even further. I know some people show a very limited persona, or perhaps a different side of themselves on their blog, but for me it's WYSIWYG. I've even used it as a reference in singles contacts - telling someone if they want to know more about me, read what I have to say.
The challenge is trying to post regularly - but my contract is not being renewed so I may really be retired - with all the accompanying spare time. Ha!