*It's considered bad form to just publish your blog posts -- folks won't follow you if you ONLY do that.
*Twitter feed -- will automatically post blog posts.
LA Fire Dept is twittering! Crazy!
Used here in MN in 35W bridge collapse. Wow, I didn't know that.
RSS feeds... JSON, XML, RSS, ATOM (four things I really don't know much about--e)
FB is not doing this (except for the "status" feed)
Seesmic: video tweeting. Record short video, people follow you, you follow video (gives you a url so you can share with other people.) This could be really interesting for live events... also has a setting to send video urls to twitter.
Friendfeed: Aggregates all online presence--del.icio.us, twitter, fb status, etc.--other stuff into one place. Several sites do this, but this seems to be the most user-friendly one.