I ever don't use it to meet anyone new, just to keep in touch with people hundreds or thousands of miles away. And for that it's GREAT--I have several friends from college who have spread all across the world. I can't afford international long-distance bills, plus it allows for an occasional short conversation, whereas a phone call would probably be put off because it would be too much of a time investment.
But many of my coworkers use it to converse with other employees who are right down the hall, claiming it increases productivity... this is a bunch of crap as far as I'm concerned, I don't buy for one instant.