...many companies are still figuring out their online policies and how to deal with the blurring lines between work and personal time — including social networking, even with the boss.

"I think over time, an open embrace of these tools can become like an awkward hug," says Mary Madden, a senior research specialist at the Pew Internet & American Life Project. "It can get very messy."

One option is for companies to allow access to certain sites but limit what employees can do there. For instance, Palo Alto Networks, a computer security company, recently helped a pharmaceutical company and a furniture maker open up social networking for some employees, but limited such options as file-sharing, largely so that sensitive information isn't transferred, even accidentally.