Once upon a time, the classified section of the newspaper was the tool of choice for employers looking for hardworking new employees. This approach ruled the roost for generations, going back to when papers were turned out on hand-crank printing presses. When I was in recruitment advertising, around the time the millennial digits first flipped its zeroes, help wanted ads were still big. Although a lot of companies were dabbling with Monster.com or even Craigslist at that time, they were still treated more like mad experiments than key elements of an effective recruitment campaign.

Fast forward, and those times look almost quaint now, don’t they? Well, maybe not so much for newspapers, which have never recovered from the loss in revenue. But online, things are flourishing. Monster’s hugeness not only spawned plenty of copycats and niche sites, but there are other alternative (read: little or no-cost) online resources now too. And leading the pack is today’s latest trend in hiring: social recruiting.

Makes sense, when you think about it. Applying for a job usually involves submitting a resume and/or portfolio of work, not to mention references too. Why not hit up something with the references, background and other details built right in, via one big, searchable virtual location?

The leader in professional online networking is indisputably LinkedIn, whose hiring solutions segment has ballooned up to $58.6 million in Q2. Although that pales in comparison to Monster.com, which has $270 million, look at it this way: This big kahuna grew 25 percent from the same quarter last year. LinkedIn grew 170 percent. That, friends, is what you call a trend.

Where this trend might be going next, however, is what’s making people uncomfortable. Apparently, more companies are beginning to look to Facebook to find job candidates.

Here’s the thing: LinkedIn basically bills itself as an online business tool, so recruiting there makes a world of sense. But Facebook? That’s where people connect with school buddies, perhaps reminiscing about getting busted behind the gymnasium, or air out their political, religious or other beliefs via some shared linkage. So is it really appropriate for companies to ferret out potential employees on this platform?

No, it’s not, says a recent focus group run by Adobe Systems. Despite user-definable privacy settings, participants still said they were spooked by the idea of hiring managers reaching out to them on Facebook, finding it “invasive.” That may be because some people (myself included) prefer to keep their professional and personal activities separate.

But the line between them is starting to get blurred. So far, few employers are engaging in Facebook recruiting (at under 1 percent), but the site’s 750 million+ userbase, zero cost, and qualified leads could prove too tempting for them to resist. Already Monster has a Facebook application for recruiting and professional networking, as does BranchOut. And VMWare is about to launch a new Facebook app for its own hiring trial a new BranchOut Facebook app for hiring purposes. [Updated: VMWare will be a beta tester for BranchOut’s RecruiterConnect product.]

According to Will Stanley, VMWare’s talent acquisition Web strategy manager, candidates are twice as likely to apply for jobs found on Facebook compared to other ways.

Do you find this to be true? Are you more likely to apply for a job found on Facebook? Or would you rather keep your work life out of your online social life? Let us know how you feel about this, as well as how you’d go about job hunting now. (Facebook? LinkedIn? Monster? Other?)

[via Wall Street Journal, image via James Yang, WSJ]