An iPad set up Saturday night for anyone to tweet from the protest.

Demonstrators down on Wall Street for the 'Occupy Wall Street' campaign as well as interested parties following the event online were wondering why the hashtag hasn't broken into Twitter's trending topics list, which right now feature Radiohead, Doritos and #thechew, a new talk show. Considering there is evidence that Yahoo is blocking emails about the protest with a message about "suspicious activity," it was suggested that Twitter was also censoring the topic.

Not so, says Twitter's Carolyn Penner, who pointed us to this blog post, written after people made the same speculation about the #wikileaks tag, which explains that Twitter's trending topics are based on what's breaking out rather than what's popular. "Twitter Trends are automatically generated by an algorithm that attempts to identify topics that are being talked about more right now than they were previously," it explains.

Sometimes a topic doesn’t break into the Trends list because its popularity isn’t as widespread as people believe. And, sometimes, popular terms don’t make the Trends list because the velocity of conversation isn’t increasing quickly enough, relative to the baseline level of conversation happening on an average day; this is what happened with #wikileaks this week.

Protesters have been using #occupywallstreet, #occupywallst and #ows to collect tweets about the demonstration.