This question lies behind an interesting recent article, "The Scholarly Apparatus: When Should it Be There?" by Harrison Eiteljorg II in the CSA Newsletter of April, 2010. He takes some archaeology websites to task for including scholarly information but no attribution of author, date, etc.
I agree completely. Without the "scholarly apparatus" such websites are fluff, not scholarship. Even entries in Wikipedia have authorship (although you have to track that down, and it's not always completely clear).
There is also a page with reader commentaries.