[Business Goal] Brand advertising [Typical Key Metrics] Reach and frequency, e.g. unique users and views of your Facebook application or Twitter followers Engagement, e.g. number of comments or links on a post. Share of voice Quality of the audience that you are reaching, e.g. demographic fit [Description] 
Even though the biggest opportunity with social media is thought to be in facilitating conversations, it is obvious that many marketers are still approaching social media in a way that is more similar to traditional advertising or PR. Companies doing this should then look at typical advertising metrics to measure and improve success