or automatically placing everything posted in the public domain?

No. Just because I can publically access http://perlmonks.net/index.pl?node=Tutorials does not mean I can repost the contents without permission. Same goes for forums. Since perlmonks does not explicitly require you transfer copyright, the poster retains it.

ok, cool. In this example tutorials is considered a part of the "infrastructure" of the site, but in a public forum, where things are publically posted, i figured the post would revert to the public domain.

Update: I posted a little too quick, and had a look at dictionary.com. My understanding is the owner retains copyright on his/her work(s) unless explicitly stated otherwise. So, unless there is some kind of disclaimer with the work, its all copyrighted.

To tie threads together: an option for The Monastery is to provide the service of hosting messages in exchange for a permanent, non exclusive licence to display, in their entirety, any messages which have not been deleted before the expiry of a period of thirty days from the time of their submission. This general licencing agreement does not preclude any other agreements being executed between The Monastery and any user or group of users.

Some lawyer or paralegal can turn this into legalese. Or maybe someone from the SCA can translate it into latin.
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