That said, I guess we do need to clarify the legal status of everything he's made now. Jgarzik, could you please publish a license or at least go on record with your feelings about copying and/or modifying your works? Do you require attribution?
If you don't, a lot of people (myself include) will naively (and possibly incorrectly) assume that you intend all of your code and documentation to be released under a permissive (MIT or BSD-style) license.
All of the code I've released is under the same license as bitcoin itself. Copy away, it's open source
I'm undecided about the documentation, but RHorning is way out there: it's ridiculous to think anyone will "take over" the protocol by writing a document and keeping it on their own website.
As long as Satoshi distributes the code, he "owns" the network protocol, and I hope it stays that way!
I think documentation should be released under some permissive open-source style license. That way others can correct potential mistakes, add info that you left off, etc etc and publish it back under the same license. Essentially, we should apply the FOSS philosophy to documentation.
That said, I agree that you have the right to prevent people from copying your works exactly if you so choose. You really can't stop them from using it to produce a derivative work, though - after all, how would you know they didn't just read the code themselves?