I haven't messed around with FB's instant messenger yet (if that's what you're referring to) but I guess you could say FB is similar to CL in many different ways.
Their messenger isn't something you should mess with. They have a warning system. I was sending the same link to a friend of mine over and over and over again one night. Maybe like 20 times in a matter of a minute. Well I kept getting a warning message, they essentially limited my chat for an hour or so and yeah, not something I want to risk doing again. I'd suggest finding out the rules of messaging or trying them out on an account you could afford to have banned.