WWE Twitter works for a number of reasons: It is interactive, personal, empowering, and engaging.

For American Airlines, Twitter is a customer service tool. With more than 416,000 fans, it ranks fifth place among airlines.

Delta Airlines uses Twitter to go beyond social marketing by providing customer service to mid-flight customers.

With more than 150,000 followers, HP’s site is clearly the winner -- more than triple that of Dell and six times more than IBM.

Southwest is one of the most prominent brands on Twitter, clocking in at over 1.3 million followers and fans around the world.

The store is the 11th most popular corporate brand on social media, with more than 400,000 Twitter followers.