Meeting online is a relatively new way for folks to hook up, which means there isn't all that much conventional wisdom out there about the subject. Both people must feel fully comfortable with the conditions, and have a way out. You get to know the person before drawing judgments on appearance.
People also seem to be more open about themselves when safely behind their computer screen.
Those who choose to lie about themselves. Overall, I'd have to say that meeting people over the net has expanded my circle of friends. I met a wonderful person in a chat room in May of 1997. She and I arranged to meet in July of 1997 and we have been seeing each other ever since. Our relationship has developed since then, and we are discussing whether one of us should have to move to the other's location.