Facebook, always ahead of competition, just started a blog feature. While the Wall is a place to write notes to others, the Notes is the place to write on your own page.
You can edit or delete your posts and people can comment. I do not see any kind of e-mail notification for comments. Spam should not be a problem as the Facebook is a closed community. Interestingly, if you write about another person on Facebook, you can do a tag, so that person knows that you have mentioned them.
The best thing is I can use the RSS feed of this blog and use it as my Notes. It looks just like in any newsfeed and whenever I put something under the fold, people can click and come over here to read the rest of the post. Neat!
Techie blogs are commenting on the Notes already quite a bit. This blogger posted some images so you can see how the thing looks like in case you are not on Facebook.
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