Twitter got its start in 2006, first with Jack Dorsey and then Evan Williams as CEO. In 2013, its CEO was Dick Costolo, a former Google executive, who steered the firm through one of the most exciting times in the firm's young life. Since its inception, the social network that lets users send short messages or "tweets" 140 characters in length has attracted world leaders, religious icons, and celebrities as well as CEOs, marketers, and self-promoters. When the firm was in anticipation of going IPO in November 2013, It had 230 million users with three quarters outside the United States.

How would you choose the comps to value Twitter at the time of IPO?