I love LinkedIn. But I do not trust LinkedIn. For recruiters, it’s obviously a key tool, and clearly a brilliant invention that is part of a seismic shift in the way recruitment works. I wish I had invented it. But I believe, that for agency recruiters, LinkedIn is not your friend.
via Can we trust LinkedIn? – RecruitingBlogs.

LinkedIn is no better or worse than any other source.
You need to make an individual assessment.
The main difference with LinkedIn is that the active job seekers and recruiters are not hidden amongst those poor souls who can wait to tell the world what they had for breakfast