I do not know if this has already been done, but I think that there could be an option that is that only those on your friend list can comment on your profile. Just an idea! =)
Very good idea, wish that it could be possible, but... What of those that don't have any friends on their list? And just clicking on invites doesn't help either, because the 2nd person doesn't have that person on their list. For this to work, they must already have people on their list.
I believe it has benn suggested all ready,but I think it sa good idea. But what if somone wanted to be your freind , and they could'nt ask if they could add you.
That's the thing I'm trying to get through here. What about those that don't have any friends yet? The option to toggle the block would be good, but for this to actually work for a person, they need to first have friends on their list. I would go with other PM ideas, but that might infringe the users' privacy; you really don't know that person until you meet him/her.