Preventing anonymous users from posting prevents heavy spam and some specific individuals from coming back and flaming.. so having anonymous posting (where one does not have to register) is a very bad idea.
I think we have to bring in the risks/benefits analysis. I really think that blocking the IP is no good. I have some guy who continuously spams my blog and he has many different IP addresses. The risks clearly outweigh the gains.
lolz yea it would be obvious if it was like "SPAM SPAM SPAM SPAM SPAM SPAM SPAM FREE IPODS FOR FREE JUST SIGN UP ON THE FORUMS SPAM SPAM SPAM SPAM" but most posts go to the hardware and software section
Just A Guy With A Voice In His Head...