I think that online activity like contributions to forums, twitter and github could be good indicators of a quality employee. However, I know many really smart, productive people who just aren't participating online in a significant way. If you're hiring for a community liaison then online activity is a critical indicator. If you're hiring a network engineer who watches log files and traffic all day online activity may not represent their "best self."
Agree 100%. Our approach is "if a candidate has some data online, we'll help you make better sense of it. If they don't, there's nothing we can tell you."
