This is actually a big deal for Facebook. 20 years ago, no one would have really cared WHAT teenagers considered "hip". The reason was, teenagers had next to zero buying power. Teenagers were trying to act like "grownups". Now, take a look at any of your teenager friends/family. They're standing there in a mirror with a brand new iPhone and a Macbook Pro in the background. Now look at a picture with their moms and/or dads. Notice that much of the time, the adults are trying to dress like the kids. The kids now represent an enormous potential as the adults are just dying to hold on to their youth. For now it's wise for any company that wants to turn a huge impulse profit to pay attention to what the fickle teen generation is currently considering cool. Vine is a perfect example.