Founder, Altimeter Group
Since leaving Forrester Research in 2008 to start Altimeter Group, Li has been pulling in big clients (HP, Microsoft). She has a history of staying ahead of the curve: She got into social media in the mid-1990s and was one of the first industry analysts to blog. Her firm focuses on disruptive technologies and is running a social commerce conference this fall to look at how social media is shifting power between consumers and retailers. "Nobody looks at the boring side of the business when you're in social media," says Li, 44, "but it has huge impact." --B.K.
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Last updated July 09 2010: 1:19 PM ET