This comes after the LA Times' experiment with a 'wikitorial' went awry. To quote from The Guardian:
"At first the comment piece evolved sensibly. But once the newspaper's online monitor had gone to bed all hell broke loose. Discussion of US exit strategy from Iraq gave way to 'Fuck USA' and hardcore pornography. The feature was pulled after 48 hours.
"The newspaper, cheered perhaps by the high ratio of encouragement to derision in bloggers' post mortems, has promised to revive the idea with better policing."