Am thinking we need to bring in the "down vote". The majority of people are decent and will not like spam, porn, etc. The client can then pre-screen on upvote/view ratios.
Discussion
I can see a vote system being a good way to discourage low quality posts by a single person, but when it comes to automated spam in high volumes, i don’t think manual voting by users can keep up.
Automated spam needs an automated deterrent.