Scoble's 5 reasons why blogging is hot.
1. It's easy, anyone of any expertise can publish
2. Discoverable - pings weblogs.com, movabletype site, other sites that aggregate blogs
3. Ascertain social behavior, trends, linking, know at all times what's being said about you, and who's talking about what, in real-time.
4. Permalinking - each post has its own URL - can link directly to timely, relevant, and focused content
5. Syndication - only read what's published, when it's published - when I 'subscribe' to you, you're now a member of 'my community' - I don't need your email, you don't need mine, and in our normal day to day publishing, we're connected. For as long as we want to be - it's a pull relationship

At the end of the day, all of these things support relationships.

A blog is a web page that has content published in reverse chronological order...

Title your blog properly. Why? When our blog shows up in a list, or is aggregated on weblogs.com, technorati, feedster, it's impossible to use some of the titles that exist for most blogs. (it takes an average of 8 minutes for your post to show up in Technorati)

Look at Tompeters.com for an example of how the website becomes the blog and the blog becomes the website.