Thank you, and they can — like stevelosh says, there is a checkbox when you add or edit any post that allows anyone who knows the URL to see it (sans comments, though).
I meant to say that I wish there was a way to get a listing of all my public posts without having to log in. Kind of like going to someone's Twitter profile if you aren't logged in.
Just a very minor nitpick, it seems like you have a great community so far which far more valuable than features that can easily be added, keep up the good work!