Dive summary: 

• The 2013 Grammy awards did a commendable job utilizing social media and provide seven takeaway lessons for organizers of other events [see full list at CNET]
• There are six things the Grammys did right including be semi-obnoxious, tell the audience what they will get from following you, let people know you're listening, spell it out letting people know exactly where to find you on social media, be active on social media accounts during event, and think about social media long before event. 
• One area for improvement in the Grammy social media strategy, and the seventh takeaway, is to help your audience keep up with the fast pace; the Grammys could have provided musicians Twitter handles to viewers keep up. 

From the article: 

"All these activities seem to have paid off, as Grammy related hashtags were trending around the world and continued to do so hours after the show ended. According to stats provided by Twitter to Mashable, there were about 13.2 million tweets during the show..."