Facebook: You’ve got a friend or foe?

Facebook — the best invention since the Clapper or the devil's favorite device? Today we hear both sides:

SUSAN: I'd been searching for my best friend for nearly 20 years, ever since a misunderstanding led to an estrangement. Even though I found a city listed for him on the Internet — the last city I had an address for him — I figured it was old news because he was in the Marine Corps and he couldn't possibly still be stationed in the same town for so long.

A few days after I joined Facebook in 2009, I typed his name into the search, and there was a guy with the same name on the opposite side of the country. The picture with the profile looked enough like him that I …