General

The Internet is great for finding POTENTIAL people. But in a place where people lie about their gender, age, looks, etc., I would not consider anyone more than potential until I meet them. Even if they are honest, you can not get the feel of what another person is like until you meet them.

I agree with all the limitations everyone has described here, and I want to add one more:

It's too easy to blow someone off online. All relationships hit rocky points, and individuals hit rocky points where they don't want to deal with others. And in those moments, people online just disappear. They ignore the person they professed to love just a few days ago.

The ease of behaving badly makes this medium not conducive to a full-blown relationship.

Another advantage of the Internet is that you can get to know the person inside without being distracted by the person outside. If someone is not very attractive, it may be possible to really like them and being able to overlook their looks or other distraction.

My suggestion is to meet anyone who is near, and forget anyone who is not near. I know someone will have a good story about someone they met half way around the world. But this is very risky. One person has to give up their home, their family and their job to be with the other person. And if it does not work out, that person is totally left homeless, jobless, and friendless. It also puts two strangers together and almost impossible to split up.