CEO Dick Costolo, in the investor hot seat, makes a case for the social network’s growing momentum. By Ainsley O’Connell February 5, 2015 Twitter CEO Dick Costolo was full of renewed brio today as he reported the company’s fourth quarter and end-of-year 2014 earnings. “We closed out the year with our business advancing at a … Continue reading Twitter Beats Fourth-Quarter Revenue Target, Falls Short On User Growth