Remember a few months ago, when lots of bloggers (including yours truly) were all in a tizzy about studies that seemed to suggest that teenagers are leaving Facebook? And therefore Facebook is doomed, doomed, doomed I say? Well, that's not necessarily true, judging by a series of more recent surveys. The latest data comes from Niche.com, which surveyed 7,000 graduating high school seniors to find out about their social media habits. Guess which social network came out on top in terms of daily users?