I first met my girlfriend of three years online. It wasn't through a dating website or anything like that, we just kept running into each other on a video game/sci-fi message board somewhat like this one. Eventually, we starting getting to know each other, and things just kind of took off from there.
I can't give my opinion on sites that are specifically designed for dating 'cause I've never really used one, but I think love can blossom over the Internet. It needs to move past that and into the real world at some point, of course, but for a start, it isn't as bad as it's made out to be. Sometimes, it works.