But Facebook has mostly become a place to reconnect with former classmates, long-lost friends and family members. One week a bunch of former college-mates came out of the woodwork. Then it was everyone I worked with earlier in my career. Then everyone I went to high school with materialized, followed by people I went to grammar school with. Meantime, one family member after another signed up, and now we connect through Facebook more than we ever did by phone. (That's especially the case for me. I was never particularly good at keeping up with family by phone, but I zip them Facebook messages much more often.)

With all of this cross-activity, I have to stay sharp in case some hacker sends me a message claiming to be an old classmate or a PR person with a security story to pitch. Sometimes we click on URLs without giving it a second thought. But in the virtual world, we can't do that anymore. The dangers are too great.

Some PR folks will see this as an opportunity to barrage me with e-mails whenever there's a way to work Twitter, Facebook or LinkedIn into a scary pitch. They shouldn't bother.

My view is that social networking sites have always been at risk. The recent Twitter headlines make this look like something new but it isn't. So PR pitches on this will likely leave me cold.

That said, social networkers need to take care when wandering around these sites and run away whenever someone on these sites asks for their credit card number or any other personal information.

Think of it this way: The virtual world has more or less fused with the real world. If you are on Facebook, you are visiting real neighborhoods and traveling real highways.

One must be as careful navigating these places as they would if they were venturing down a dark alley at night.