You have to love Youtube...
A little off topic on what you meant, but wow at the whole YouTube community. I always thought of YouTube as just a video sharing website, but it's so much bigger than that.
All the exclusive communities, YouTube only series along with response videos, rivalries, etc.
People who make a living just posting home made content and now with the gaming stream and chat... It's like Facebook, but only awesome. Definitely a better association with the term social media than Twitter or FB.
So much entertainment and you can definitely get lost for hours watching stuff.