I think that online dating sites have their purposes. For someone like myself, who lives a fairly busy life with my schoolwork, research, and other commitments, there is not much time to go out and meet people. It is especially hard when, as is my case, you are a very shy person and also have moved from PA to Orlando, FL. The other thing for me is that where I go to school, it is hard to meet people without a car and without being able to go to a bar or a club, and in my case, not having a car and only recently turning 21, I have had little alternative other than online dating. It has worked fairly well for me, I have gotten to meet a few fun people and had a good time doing so, but nothing substantial has come out of it, since it seems that when I do get to meet the person face-to-face, as is usually something I find very important in getting to know someone, things seem to fall apart, but that has little to do with the online dating itself, rather with my personality.
All that being said, of course, it is not the right solution for everyone. A lot of the most legitimate sites charge a lot of money for their services, so that is also a factor that turns people off. The other thing is that some people just do not need the help of the internet in meeting people, I just happen to be one of the ones who does, that is why it has sort of worked for me so far.