Borrell recently reported that:

Still, the potential for growth is huge. Unlike autos and real estate, where the majority of purchases are already directly impacted by Internet search, Borrell cites CareerXroads data showing that only 13 percent of U.S. adults currently use the Internet in a job search – although the Internet accounts for 25 percent of external hires.

Not sure why this should surprise anyone—the current job boards are really databases of resumes, not a way to find your next job.