We can’t help with the first two questions, but we can consult one of YouTube’s inside men about the viral video question. Kevin Allocca is YouTube’s trends manager (he says he professionally watches YouTube videos), and recently he gave a talk at TEDYouth about the reasons videos go viral.
Alloca said three things are behind viral videos:
Tastemakers. The people with large social media followings—a celebrity or so-called influencer, for example—who share a YouTube video and make it go viral. Late-night host Jimmy Kimmel did this with the now-famous “Double Rainbow” video.
Communities of participation. This refers to when a group of tastemakers take a point of view and share it, which is kind of like steroids for a YouTube video. Soon, they’ve created a community around an inside joke, of sorts. For instance, the Rebecca Black YouTube sensation “Friday” became so popular because a community of tastemakers rallied around it, poking fun of it, parodying it, and so on.