For finance professionals, a carefully crafted résumé has always been vital to landing a job. Now some experts say that social-networking Websites have become just as important to a successful job search, if not more so.

Millions of people have posted their credentials on such Websites, and companies are increasingly using them to find and scrutinize job candidates. In a recent survey by JobVite, a vendor of recruiting technology, 83% of employers said they are using or plan to start using social networks for such purposes. Among the 58% of survey participants that had already hired through those channels, 89% used LinkedIn, versus 28% for Facebook and 14% for Twitter.

A December survey by a more disinterested outfit, the Corporate Executive Board, offers corroborating evidence: about 80% of companies polled planned to increase their use of social media for recruiting in 2011.

Job hunters and hirers who are not using LinkedIn or similar networking tools are missing opportunities to connect with one another, says Ali Chambers, vice president of outplacement at executive-coaching firm ClearRock. Indeed, labor markets have always been inefficient at matching up employers and candidates; the 2010 Nobel Prize in economics was awarded to three academics for their research on that topic, much of it decades old. But as social networks grow, labor markets promise to become efficient one day.

On LinkedIn, job seekers can not only provide information about themselves and their work histories, but also list their connections, their recommendations, and the discussion groups they belong to. “It has more texture than a résumé,” says Chambers.

Recommendations are particularly valuable for such high-level employees as CFOs. “Having people at very senior levels giving testimony to your accomplishments — how you add value and solve problems — may differentiate you from other candidates,” says Chambers.

Given that many finance chiefs already have considerable visibility without social networks, such Websites are probably more useful for people reporting to CFOs, such as those in financial reporting, financial planning and analysis, treasury, internal controls, and mergers and acquisitions, says Peter McLean, chairman of the financial officers practice at recruiter Korn/Ferry.

McLean agrees that LinkedIn is an important tool for job seekers, likening it to online dating sites as a mechanism for connecting people. But he disputes the notion that social networks are as important as a résumé. “That’s an overstatement,” he says. “Your résumé is ultimately what’s going to sell you, or not.”

Not surprisingly, LinkedIn finance chief Steve Sordello has a different viewpoint. Speaking at last October’s CFO Rising conference in Las Vegas, he said the size of LinkedIn’s member base — 80 million, with a million more members arriving every 10 days or so — creates transparency that is useful for employers. A person can exaggerate his credentials on a résumé, he pointed out, but on LinkedIn “you’re online for everybody you ever worked with to see. It’s hard to exaggerate.”

That doesn’t mean it’s impossible to do so. McLean says some people do stretch the truth on LinkedIn, but not many. The vast majority present legitimate credentials, he says.

Another interested observer — Barry Libert, CEO of Mzinga, a firm that provides social-media platforms allowing companies to connect with their employees, customers, and partners — says it’s clear that social media have already eclipsed résumés in relevance. “In a world where hundreds of millions of people are connected to each other, your social-media presence, profile, and activities are your résumé,” he says. “It is you. Your interests, passions, friends, network, and personality are all there. It is far more valuable than a résumé.”

Meanwhile, it’s not all about LinkedIn. Chambers says Facebook and Twitter both have enormous potential to become important tools for job seekers and employers alike. They’re moving that way now, she says, and both platforms will likely develop job-search apps for use on mobile phones.

ClearRock, meanwhile, offers several tips for building an effective social-network profile:

• Position yourself as an expert in your field. Include searchable keywords that detail the depth of your professional experience. Employers search for not only employees per se on social-media sites but also solutions to problems. Your expertise may be what a company is looking for.

• Stay active. Join LinkedIn and Facebook discussion groups that are composed of people in your profession or industry as well as targeted employers, and post to them regularly. The more you do, the more often your profile will be viewed, and the higher you will rank when potential employers are searching for someone like you. Answering questions from group members and commenting on the latest trends is a way to stay current.

• Watch out for any discrepancies between your résumé and social-media profiles. Such details as dates of employment must match exactly. Employers will pick up on any inconsistencies right away.

• Include your LinkedIn URL in the signature block of your e-mails. This will encourage people to click on your profile.

• Make sure you have a public profile setting so that your profile can be readily found on Google. Adjust your privacy settings to accept InMail, a service that executive recruiters often use.

• Devote a Facebook page to your work as a professional, separate from your personal page, to use in your job search.

• Keep your profiles up-to-date. Give meaningful status updates, such as links to your blog, and include your job search in status updates with your connections.