My friend, Diana Birchall, has announced she will try to blog regularly, each Monday and Friday. I think it's a lovely idea to blog regularly -- if you enjoy it. If it's gratifying to you and fills a need or if you want to reach out to people and become part of a world, whatever world that be.
If you begin with a readership -- as both Catherine Delors and Diana already have -- it can grow. And not to be discouraged if you get only brief or no replies sometimes: as on lists, the world of cyberspace is filled with people who read others but do not post themselves. My two blogs are on wordpress and live.journal and both have ways one can find out how many "hits" one had a day, and I notice these do go up when I blog on a popular topic (Austen say or a recent movie), though sometimes I am puzzled when a blog gets a lot of hits I didn't expect. Or you can post to a listserv about a blog whose matter is of interest to that listserv (but you feel what you wrote is too long or involved to send to the listserv) and then readers from the listserv come over.
One way to get a larger readership is to aim your blog at a "niche." Catherine's is aimed at French 18th century history and historical novels or novels in general. Just about all her posts are about this. My friend, Judy, has two blogs, one on costume drama movies and the other "classic" movies. She is consistent about it, all her links are to other blogs on these two respective topics and she has gotten a readership of others like hers. Her blog is part of a circle of blogs now. There are many many Austen blogs. There are poetry blogs where people post about poetry or poems.
For me this doesn't work. I can't get myself to blog to a narrower niche -- I'm not into conveying information for information's sake on a topic (which I find some bloggers on narrower areas do); nor am I commercial (Teach Me Tonight is a commercially oriented romance blog); nor am I news-oriented (Austenblog is a newsletter in effect). So my "Reveries under the Sign of Austen" is frequently not about Austen (though it often is), but topics I think relate: by women authors, on the 18th century, similar film adaptations, on Austen criticism. And I like to blog autobiographically seasonally. I like life-writing, diary writing. There's nothing wrong with that; you don't have to bare your soul to write in the diary journalizing way. And I notice some readers will come over to read "you;" that is, they came over to your blog because (like a columnist) they like your tone, presence, kinds of statements and so on. I read friends' blogs.