The biggest threat to privacy, is how little (most, nearly all) other users do NOT value someone else's privacy.
Re Spam: Pre-screening, and people that actually say something useful to the (automated) screening service. Actual spammers should get fed to a blacklist (filtered for multiple confirmations), and organizations that prosecute spammers should be able to read THAT list. Everyone else has to use a more public API that's rate limited.
Re Spam: Pre-screening, and people that actually say something useful to the (automated) screening service. Actual spammers should get fed to a blacklist (filtered for multiple confirmations), and organizations that prosecute spammers should be able to read THAT list. Everyone else has to use a more public API that's rate limited.