I'll start with a question: When a user publishes a PEP item [1], should the server send notifications to appropriate contacts that appear offline?
I've been told that the answer is probably no, it shouldn't, which makes sense. The first potential problem here is that this isn't explicitly stated in the XEP and maybe it should. The second potential problem is that I believe this behavior clashes with some mechanisms that rely on 'faking' offline presence (i.e. blocking, invisibility). For instance, when userA becomes invisible to userB [2] he will appear offline to him. Then, if userB updates his avatar (publishes a PEP item) userA doesn't receive the corresponding notification. This seems like an unwanted side effect. If invisibility is an option, I think that the expected behavior from a user's perspective will be that everything works the same except for the offline appearance to others. Gabriel [1] XEP-0163: Personal Eventing via Pubsub, http://www.xmpp.org/extensions/xep-0163.html [2] XEP-0126: Invisibility, http://www.xmpp.org/extensions/xep-0126.html
