For the second part yes. I wouldn't want every single chat on someone's profile wall to be entered in the chats. Notifications or mentions would be allowed but I would like to ensure that people profile walls chats don't turn into whole conversations. My intent for Profile chat walls would be for the profile owner to use it as a way to leave messages for fans, friends, and followers. It's to also have more people go onto other people's pages promoting interaction if they are forced to go onto someone's page.