Pardon me for cutting in... been following this thread a little bit, Jeh.
And - forgive me if I'm stating something you already know - the difference being in the definition of the words.
= like, when you see the symbol (C), possibly with a date and next to the author's name -
it simply means that the author has put his/her creation in either written or recorded form - either or BOTH, actually;
and the author has signified OWNERSHIP rights of that piece. It does NOT necessarily mean that the author has legally
REGISTERED that work with the government office: which is the Library of Congress - for which there is a fee.
2) Registered Copyright
= involves and includes THAT process of filing the appropriate documentation (or mp3) for the piece you want
to PROTECT for yourself. There is no freebie with that process.
It is my understanding, and Casey's reply was likely along the same idea: many writers do not bother with the REGISTRATION step, since the theft rate for such works... AND the legal costs involved for you if you want to go after somebody who uses/steals your material without your permission.
The costs involved in the chase rarely, if ever, meet the level worth the time & money... unless you are Paul McCartney, or any other multi-platinum person who is getting ripped off - for financial gain.
Hope that helps. I gave it a shot.
Maybe when you've written such a mega hit, and you can afford $400/hour attorneys to work for you...
get what we're sayin'?!