I don't really believe the same network can carry its metadata. (attached directly to the content) I mean, in an ideal world it would be great, but in practice how would that work? You can copy anyone's metadata to the file you published. How can anyone tell a difference? (unless you put some kind of signed ranking system on top of that, but that's just another layer waiting to be abused - like kazaa's star ratings)

It's basically the reason search engines stopped trusting meta tags on the websites.