As we all know, not every tale of an on-line meeting has a happy ending.
People lie on-line just as they do in real life.
If so, then you can rely on it here too. If not, proceed with caution, and perhaps turn to a friend to help you evaluate someone you've met on-line. Use tools wisely. Use e-mail to get a sense of a person before you meet in the real world. Learning about a person's connections with others is an important way to determine who they really are.