Before deciding which social platform to invest your time, energy and resources it's important to understand why people use social networks in the first place. To that end, here are a few resources I revisit often when developing social media strategies and mapping digital ecosystems.
For the record, gathering the data needed to make informed decisions doesn't take place on the computer. You actually need to both observe and talk to real people.
There are no shortcuts.
Paul Adams discusses the connection between content and social behavior.