Lalaguayaba

I haven't had any problems at all. I've met a bunch of really nice ppl through the net; ppl to go to concerts with, go to art gallery openings, etc. A few dates, but I seem to have much better luck on my own--the ones I've met online tend to be way too straight-laced for my tastes.
As far as precautions; well, meet them in public--not at your home, don't meet in a darkened alley, don't give them your credit card #s to make reservations, and don't have high expectations! Other than that, I wouldn't worry too much if you are using a legitimate personal ad space, I don't think that ppl are using Craigslist (not legitimate, and not policed) to meet a date.
As far as meeting someone from the net in a public space; what's the worst that could happen? They're ugly? Uninteresting? Utterly and completely boring? Statisically, you are more likely to break your neck falling down your own stairs than be followed home by a crazed internet date!

Cheers.