Blog Directories

There are thousands of search engines (and website directories) but you really only need to concentrate on getting your website listed in a few of the big boys, namely Google, Yahoo, and I suppose DMOZ. Are there a few equivalently dominant BLOG directories that have more importance than the thousands of others?

I realize that there are specialty blog directories which could be valuable. Such as being listed in a blog directory that matches the subject of your blog, or in a directory of blogs by location like a specific city or state. But are there any essential general blog directories that are worth getting involved with? A quick google search reveals blogarama, bloghub, blogcatalog, and hundreds more that all seem to be nothing more than unimportant, self-serving, linkback exchanges. Am I wrong about that?