one of the reasons why iTune's social media Ping failed was because of too much restrictions and censorship. People join social media mostly because their friend's are already there or because they want to create something on the new ground. Flags are good to mark plagiacism but if people will get restricted only because others don't like what they have to say, it doesn't make any sense... It's not what freedom of speech is and if people will get restricted too much just because others may not like it, they will just leave