An article in SIPA Hotline (10/16/09) suggests that a way to measure the effectiveness of social media is to track certain metrics before, during, and after the social media campaign.
The metrics to be measured can include:
>> Traffic to web site and blog.
>> Number of brand impressions per month.
>> Percentage of content clicked through.
>> Percantage increase in site-return visitors.
>> Percentage increase in followers or fans per month.
It also recommends monitoring what is said about your company on social networking sites using a new service called filtrbox (www.filtrbox.com) and responding to negative comments to correct perception.