I guess the key to any kind of relationship, be it lover or friends or whatever is to simply be observant and take things step by step. These kind of things build and grow rather than explode. If it does explode or something just seems out of place or too good to be true, it's probably a trap >.>
But really I give props to those who make good friends, or have the will and patience to meet each other IRL and go from there. More power to them. Too bad most people are generally crazy and/or deceptive.