Tags and Multivalence
Elin points out that the Flickr community is in the process of rediscovering an old hypertext maxim: Multivalence is not a vice.
Tags are words, and words don't mean one thing. Pages don't have a function, so you can't tag them concisely or accurately or sincerely. Pieces of pages don't mean one thing, either: the fact I offer you is intertwingled with my motives for offering the fact and your motivation for belief.
Elin also observes that the voting dynamic is itself gameable:
A common survival tactic is to be nice to people on your side of the water, yet merciless, brutal and cruel to the rest of the world. This means that if you post your photo after 6:00 pm, the Europeans will already be sound asleep while your friends (whom you've gained a lot of goodwill from by leaving sweet little comments on their photos) will help you save your precious contributions. Psychology and Strategy combined: When the Europeans rise and shine, it's too late - they've lost their chance to delete your work.