I reported earlier on Fun with Metadata. Canadian law librarian, Michel-Adrien Sheppard, blogging at Library Boy http://micheladrien.blogspot.com/, has a very nice report summarizing the best ways of dealing with the metadata problem: Avoiding Problems with Hidden Document Metadata. As I said on comments, you can't just rely on the Microsoft Word by itself to clean up your document. But see the nice links that Michel-Adrien has lined up. Thank you, Michel-Adrien!