• by Erik Sass , Staff Writer @eriksass1, February 26, 2013

Here’s one for the “well, OBViously” file: 93% of recruiters said they have used professional social network LinkedIn to successfully fill positions in 2012, according to a study conducted by recruitment software company Bullhorn and cited by eMarketer. That number is up from 86% in 2011; according to Bullhorn the proportion of recruiters using social media of any kind increased from 94% in 2011 to 98% in 2012.

While hardly surprising, the Bullhorn study data is a testament to how rapidly social media can transform a discipline and marketplace: it’s remarkable to think that LinkedIn, founded less than a decade ago (May 2003) is now a basically universal tool for headhunters. Even more remarkable, 82.6% of recruiters said they plan to spend more time on LinkedIn this year than they did last year.

Of course, while LinkedIn is by far the most popular social media tool for recruiters, it isn’t the only one at their disposal: the Bullhorn study found 19% of recruiters had successfully filled positions using Facebook in 2012, up from 17% in 2011, while 13% used Twitter, up from 10% in 2011. Furthermore, 38.3% of staffing professionals said they planned to spend more time on Twitter in 2012, and 37.4% said they planned to spend more time on Facebook.

It’s also important to remember that social networks can play a big role in filling jobs by enabling informal recruitment. In fact, last year I wrote about a study from North Carolina State University which found that some 27% of jobs in the U.S. are filled through informal recruitment, with the percentage increasing significantly in step with the salary of the position to be filled.

The NCSU researchers were able to determine that the likelihood of a job being filled via informal recruitment through social networks increases 2% for every incremental dollar of hourly wages for the job being filled. Thus a job paying $50 per hour, or $100,000 per year, is about 86% more likely to be filled through informal recruitment than a minimum wage job paying $7.25 per hour, or $14,500 per year.