The nice thing about Craigslist's authentication is that it allows casual users to post easily (and anonymously) without having to create an account, but they also allow you to create an account if you plan to use the service often.

They are able to account for both types of people.

It seems if you later decide to make an account, it aggregates all your posts into a useful summary pane.

I was able to sell a couple of things using Craiglist. I was surprised at how easy and smooth it went.

Good point I wasn't thinking about the account creation part when I read the article. I have only posted once on CL and didn't create an account.