GoPro Finds Gravity, Alibaba's Post-IPO Snore, Jim Cramer Favs Twitter

It finally happened, but not as some investors might have expected it: GoPro shares tanked Thursday after the company's CEO, Nick Woodman, was granted an early release from his lockup restriction -- but itwasn't to bail on his shares, it was to donate them to his charity. Plus, volatility has taken some of the wind out of the markets' sails, but Alibaba hasn't slipped beneath its float price. And, looking at an immensely popular IPO from 2013, it's Twitter: but what went wrong for Dick Costolo? Jim Cramer says, no big problem here, and he's a buyer -- but there is someone else with a bigger target than his on Twitter shares.