I'm trying it right now for the first time. Recently divorced.
So far, so good. Met a gal last week and we had coffee. (I pushed for a quick meeting after reading Nostatic's comments in another thread) Now we've got a real date planned for Friday night.
Got a few other lines in the water. Seems like a target rich environment (a la Top Gun

).
What I like best so far is weeding out the show-stoppers (wants 3 more kids, religious nut, dumb as a rock, etc.) and allows me to focus my limited time on prospects that could actually go somewhere. If I want to pick up on random hot chicks, I can go to a bar.
The online thing seems pretty cool so far. We shall see.