There's a lot of social media out there

In reading and doing research for my 1st class presentation - Social Media Adoption in the Enterprise - I am overwhelmed by the types of social media outlets available. And humbled by my modest ability to navigate through Facebook, and now Twitter, after reading about cloud-based productivity and wikis. So that begs the question: is social media growing so fast and is it so varied that we can't keep up with it? To be continued....