I think what they say about linking is a key concept underlying the Web 2.0 "movement":
A link from one weblog to another helps provide context around an argument or point, and it is essentially a "vote of attention" from one blogger to another. By linking to another site or blog, the weblog author is saying, "I find what you are saying important enough to link to it." Linking also helps create the conversation of the Web, the critical mass of connected thought that is not available in static text.
The relevance of a site on the Web can be determined by how often a source is cited and therefore considered an authority. Links in the world of weblogs are even more important since bloggers frequently link to and comment on other blogs, creating a sense of timeliness and back-and-forth one would have in a conversation. Technorati tracks the number of links and the unique source of links to determine the breadth and readership of any author or site. Technorati is uniquely positioned in the center of this ongoing conversation monitoring who is linking to whom and which bloggers are commanding attention on various topics.
Tags are another way of sorting blogs. According to Technorati:
Anyone with a blog can contribute to Technorati Tag pages. There are two ways to contribute:
If your blog software supports categories and RSS/Atom feeds (like Movable Type, WordPress, TypePad, Blogware, Radio), just use the included category system and make sure you are publishing RSS/Atom feeds and your categories will be read as tags.
If your blog software doesn't support categories or you're not sure, you can still participate. To associate a post with a Technorati Tag all you have to do is tag your post by including a special link in the body of your post. Please note that two word tags should be joined by a "+".
I have added this blog to Technorati's directory, and added a widget that enables my blog viewers to claim me as a favorite, which will increase my rankings (theoretically). I'm currently listed with zero fans- kind of upsetting in a way! Although, doing a search for blogs about libraries yielded 1,213 results, and only a handful of them had any fans so I'm not alone.
This is also one of the more irritating aspects of the social networking thing- popularity contests. Here is a list of the Top 25 blogging librarians, as ranked by four different metrics, including Technorati. Here's what the top-ranked blogger, Jessamyn West (whose blog I have been reading for a couple of years) has to say about the whole thing.