The PBCore metadata standard is, IMHO, one of the most important and, arguably, the most progressive thing the Corporation for Public Broadcasting has ever funded. It's a necessary tool to enable public media to transition to the digital age -- assuming, of course, that public media's managers can find their way to the digital age.
Marcia Brooks is directing the project from the Carl and Ruth Shapiro Family National Center for Accessible Media at WGBH in Boston and she's written a great article on it for the December 17th issue Current, the public broadcasting newspaper. Current seems to delay posting its articles online for some reason, so the the Public Television Digital Archive has posted a copy of Get going in metadata today with this amazing free kit! online [PDF]. Nice job, Marcia, and thanks to Nan Rubin for posting this important overview.
Update 29 December 2007: I see that the PDF has also been posted at the PBCore web site.
Update, 4 January 2008:
An HTML version is now posted at Current. --Dennis