Employees who use Facebook to rail about their bosses could soon be updating their statuses to "is looking for work."

Since 2009, the National Labor Relations Board has reviewed 129 cases involving comments made by employees on social media sites, according to a study recently released by the U.S. Chamber of Commerce. In one of the most recent cases, the NLRB determined that Wal-Mart did nothing wrong when it fired a man who posted on Facebook about his supervisor's "tyranny."

Workers in these cases claim that their online vent sessions ought to be protected under Section 7 of the National Labor Relations Act, which grants employees the right to discuss wages and working conditions in order to organize collective actions.