I think I might be a little late to the party, but I just learned about Klout and it is pretty cool. Klout is a free app that uses the number of likes, retweets, +1's, etc. on a personal or organization's social media profile to determine that profile's influence. Influence is reflected by a Klout Score that will fall somewhere between 1 and 100, with one having the least amount of influence and 100 basically being the trendiest trendsetter in the universe. Klout gives each user a different Klout Score every day and it also provides users with tips on raising their influence via social media.
What makes Klout different is that it centralizes social media metrics; a person or organization can visit one page and see how influential their Facebook, Twitter, LinkedIn, Google+, and all of their other social media outlets are at the same time. The information is presented with uniform, easy to read gaphs, and Klout even shows how the influence of an organization's social media outlets changes over time.
Klout offers organizations, be them for or nonprofit, the opportunity to really examine the effectivness of their social media strategies. Businesses can look at their influence and immediately find out what works and what needs tweeking, and they can look at previous months' worth of Klout Scores to see what has worked and what hasn't. Like I said, it's pretty cool. You can sign up with Klout for free here, and learn exactly how much clout your social media presence really has.