I agree with most points in the pro article in that the anti article is poorly researched and makes sensationalist claims (e.g. all works become orphan works without registration). As River said, if someone shows up and can show a work is theirs, it's not an orphan work any more and this doesn't require registration. I'm okay with that. Provided that the person who uses the orphan work still has to have a full citation, it should be relatively easy to 'deorphanise' works, leaving the true orphan works the ones where their creators have indeed gone AWOL.

However, citation is absolutely essential. Houndoom_Lover raises a good point about things not always being signed and verified. However, if the user of the artwork is required to cite the source, they have admitted the creator's identity already, so verification shouldn't be necessary if someone pops up with proof of identity and says the work is theirs. This does have a loophole, though; what if a user deliberately cites the wrong person as the creator? Then the creator would have to prove the artwork is theirs, which is financially not viable for most.

Another concern would be that the extent of the search for the creator would have to be clearly defined. The user has to have made a sufficient effort to find the creator, or else we'd have people claiming they Googled and found nothing and so used the work. Chaos.