At one point, my advice for HR pros who were wondering about the ethics and legal exposure of digging around on candidate's social profiles was simple.
"Just ask what your CEO wants you to do in order to have the best line of sight on a candidate. She probably expects you to do everything possible to fully vet and get the best candidate possible."
Translation: Don't be lazy, and don't be weak. Social snooping is a reasonable background activity, and anyone who tells you otherwise probably isn't as connected to business results as they need to be.
So, that used to be my advice, and I guess it still is, but my approach has softened a bit for a very specific reason. 
Candidates are more aware than ever of the risks their social accounts provide, and the younger the candidate, the less likely he/she is going to have accounts that are open to the public.
Two words: Instagram and Snapchat.
Facebook, in case you were wondering, is for the olds. Not only are candidates more cautious than ever, but the younger candidates aren't active on Facebook nearly as much, which was the platform that created the most risk.
They are on Instagram and Snapchat, and they're increasingly protecting their accounts to the fullest extent possible. That means you might be able to find them, but once you land at the account, it's protected. You have to request to be their friend/contact/hombre to see what they're posting.
I think social snooping has become less important for this reason.
In addition, the youngest of users are attempting to play our need to social snoop by giving us accounts that put them in the best light possible, which is smart if they have college admission or work-related goals. LinkedIn is seeing a surge in profiles among High School students wishing to indulge admission office's need to snoop. More from the New York Times:
"Applying for admission to many American colleges already has high school students jumping through hoops.
School transcript? Check. Recommendations? Check. Personal statement? Standardized test scores? List of accomplishments? Check. Check. Check.
Now some social media experts are advising high school seniors to go even further. They are coaching students to take control of their online personas — by creating elaborate profiles on LinkedIn, the professional network, and bringing them to the attention of college admissions officers.
“They are going to click on your profile,” says Alan Katzman, the chief executive of Social Assurity, a company that offers courses for high school students on how to shape their online images.
Last year, for instance, Mr. Katzman’s company advised a high school senior in the Washington area to create a detailed LinkedIn profile and include a link on his application to Harvard. (His mother asked that the student’s name be withheld for privacy reasons.) Soon after, LinkedIn notified the student that someone from Harvard had checked out his profile."
What's that? You're worried about the digital divide and how this plays to the have and have-nots? Good instincts, grasshopper:
“Kids from privileged families tend to do more of those things both offline and online — joining school clubs, writing for their school newspaper, getting tutoring so their grades go up, doing SAT preparation,” says Vicky Rideout, a researcher who studies how teenagers use technology. Using LinkedIn on college applications, she says, “is yet another way for there to be a disparity between the haves and the have-nots.”
For high school students, LinkedIn is partly a defense mechanism against college admissions officers who snoop on applicants’ public Facebook and Twitter activities — without disclosing how that may affect an applicant’s chance of acceptance.
A recent study from Kaplan Test Prep of about 400 college admissions officers reported that 40 percent said they had visited applicants’ social media pages, a fourfold increase since 2008."
Social snooping feels dead to me. It was only a matter of time before high school students started playing admission offices as well as employers by giving the people what they want.
The kids, as it turns out, are alright.