I am sure you are familiar with most of the social media sites, but here is a partial list
Facebook Twitter
LinkedIn Flickr
Foursquare Google+
MySpace Pinterest
YouTube
There are quite a few more, however, this gives you some insight on your choices.
All of my clients use Facebook, Twitter and LinkedIn. Next is Google+ followed by a close Pinterest.
The others are used by a small percentage although YouTube is coming up in the ranks..
