10 of the best social media campaigns from 2012

Measuring the efficacy of social media marketing still isn't an exact science, regardless of what the gurus and ninjas tell you.

So how can we whittle all the thousands of social campaigns we've seen this year down to a definitive list of the '10 best of 2012'?

Do we gauge it on the number of new fans acquired, retweets, ROI, YouTube views, the number of people it reached, sentiment analysis, the amount of traffic it drove or maybe the number of new brand advocates it created?