Anonymity has a place I suppose. I am still trying to work it out for myself. As for trusted information, anonymous entries have no standing. Even within a crowd, the wisdom of the crowd may seem to enable anonymous entries and create a sense of "trust-worthy-ness". However, when you can dig deep into the data and reveal that some entries are tied to special interests, then the anonymity becomes a problem. The "trust-worthy-ness" is disrobed.
One of the key educational skills that will be required for success in the evolving world and state of information is to make sense of what can be trusted and what needs to be verified. It will require more than a sniff test.
Source of this: some coversations during the weekend at PodCamp Boston 3 and this recent link via Liz to one talented person who can uncover the identity of wikipedia editors.