"Within the past 24 hours, user-contributed link aggregator reddit.com compiled a 'secret list' of banned domains..."

"... including such reputable news sites as The Atlantic, Business Week, PhysOrg and ScienceDaily."

Reddit is a site that claims to be all for online democracy and transparency. This abrupt act of censorship has triggered a response from users—and the upset is gaining momentum by the second....

One of the reasons behind the censorship is that it isn’t being seen by reddit staff as censorship. The banned domains have been linked to accusations of reddit users “gaming the system,” or having financial ties to the promoted links. 

There was spamming and cheating. Reddit's response to the linked post was: "You can’t have democracy if people can rig the ballot box."