The only real value they provide is the anonymization of submissions -- there are technical ways to do this, but most people with information won't know about those technologies beforehand.

Authenticating the information could be done with a cryptographic signature, possibly by an unknown signer. Operate on the "last 100 0-days signed by this key when initially published were good, #101 is probably good too" basis, to build a brand.

The problem of maintaining a nice repository for the information is much much simpler, once it's already online. Google could do this for most data (just include a special string in the file), and for stuff google won't touch, there are plenty of people who would pass it around informally.