WordPress.com is perhaps the most feature-rich blogging service out there. It uses the popular open source web software WordPress, and offers many features in its free version — traffic stats, anti-spam filters, SEO, gorgeous themes and more.
Blog.com is another popular WordPress-powered blogging platform.
Google Blogger is a well-known blogging service that offers many features to its users.
Tumblr is a popular and feature-packed microblogging platform.
Posterous Spaces is an excellent online blog-publishing service that is similar to Tumblr.
Blogetery is a WordPress-powered online blogging service that offers a modest set of features.
Weebly offers more than just blogging — it’s a fully featured website builder!
LiveJournal (often abbreviated as LJ) offers blogging with a touch of social networking to it.