Back in January 2004, I was wondering whether I had time outside my job as a print journalist to maintain even one blog. With the launch of this blog on technologyreview.com, I now have three.

I know I’m not alone. Technorati tracks just over 11 million blogs worldwide, but the actual number of bloggers is probably much lower, given that many people maintain multiple blogs under a single blog hosting account, or have blogs at several locations such as LiveJournal, TypePad, and Blogger. My blog count of three doesn’t even include the pseudo-blogs that go along with my accounts at places like Bloglines and Wallop.

Why on earth would anyone need three blogs, let alone one? (It’s important to remember that many people, if they know about blogs at all, still see bloggers as suffering from a peculiar blend of folly, arrogance, and narcissism.) I think the logic comes down to this: blogs are inherently personal, and we inhabit more than one persona as we move through our days. To the extent that blogging is becoming an important mode of self-expression and social interaction, therefore, we need a separate blog for each of our personae.

My first blog, Travels with Rhody, started out as a catch-all site where I wrote about “science, technology, the Internet, and life with a dog.” Most of the stuff related to my hobbies and miscellaneous interests, but I also blogged pretty frequently about technology stories that seemed too time-sensitive, too specialized, or too weird to write about in Technology Review.

Once a group technology blog was launched on technologyreview.com, I started doing most of my technology-related blogging there, and reserved Travels with Rhody for non-work stuff. But posting there didn’t feel all that rewarding to me. It’s a group blog, which means it’s rich with variety, but on the other hand it can’t be shaped to anyone’s personality, style, or particular interests.

This spring, my assignments for the magazine brought me to the point where I felt like I needed a one-man blog where I could air a single subject: social computing, the theme of a feature article I’ve written for TR’s August issue. The interface for THIS blog (the one you’re reading right now) wasn’t ready yet, so I launched the social-computing blog as a satellite site, the Continuous Computing Blog, using TypePad as a platform. We decided to use that blog to make the August article into an experiment in participatory journalism. The experiment involved a bit of JavaScripting that would have been difficult using the main TR site, which turned out to be another good reason to start a satellite blog. And if things go right, the August article will grow into a book. So Continuous Computing is a sort of hybrid work/personal blog where discussions on social computing can continue well past August, and where I can organize my thoughts for the bigger project.

And that brings us to this blog, Tech Coast. Here, I’ll blog about all things technological except ideas that relate directly to social computing, which will go to the Continuous Computing blog. I feel like I’ve got all the bases covered (at least for now): my home life, my work-related professional life, and my non-work-related professional life. Each of these personae has different things to say, to different audiences, and there’s no reason the readers of my TR blogs should have to suffer through my musings about macro photography and doggie day care.

Now that blogging tools have become so inexpensive and so easy to use, maintaining multiple blogs is almost as easy as having just one – at least from an administrative point of view. Of course, you still need to have something different to say in each blog. But I think multiblogging will grow in popularity as people realize that blogs are far more than online diaries. They’re channels for one-to-many and many-to-many interactions, on subjects that can be personal, professional, social, political, religious, or what-have-you. If we have 500 channels on our TVs, why not have two or three Internet channels for ourselves?