Salesforce.com’s 9th annual user and developer conference – Dreamforce 2011 – takes place from August 30 to September 2, 2011 here in San Francisco at the Moscone Center in downtown.
If you are attending and want to tweet about the event, the DreamForce Conference Hashtag is
Some people have also been using another longer hashtag to tweet the DreamForce 11 / Cloud 9 Conference
From monitoring the tweets on twitter, it looks like #DF11 is the official twitter hashtag for this annual Salesforce conference. Tweet away!