This paragraph by Matt Gemmell should be printed out and hung on my wall.
I don’t think there’s any reasonable way, or any need, to separate vanity and ego from a personal blog. Writing is inherently about its author, and is a product of their personality and opinions - that’s not something to be shy about, and we shouldn’t try to change it either. So, write for yourself - and hold yourself to an appropriate standard, because you’d better believe that others are judging the person as well as the piece - but as soon as you publish your views, you’re inviting readers to take a look. I think that the needs of the reader and the author are more aligned than many blogging systems seem to believe.