Nope, not at all. We're friends on FB, but never ever post messages to each other. I can't even remember the last time I checked his profile.
Well it didn't affect me too much with my ex when we were together, but I must admit that now that we're broken up I have a tendency to check up on his facebook. I know I shouldn't, but I'm just so used to knowing what's going on in his life, and it's just so easy. I'm also worried that my facebook might be offputting for future guys seeing as we were together for a long time and had some very camera happy friends, so there are a LOT of photos of us together. Also I can imagine finding it difficult having such easy access to information about a new boyfriends past, some things you just shouldn't get to know unless the person chooses to tell you.
No, people take facebook far too seriously