This architecture works well for event based apps. For more flexibility though you should make sure the logic is in Javascript on the client and just use Flash to keep the socket open managing the xml snippets to the ejabberd server. As long as you are not pushing a lot of data between Flash and Javascript via ExternalInterface the performance is pretty good. Hopefully the need for the Flash bit will go away if Web Sockets makes it in HTML 5 (http://dev.w3.org/html5/websockets/)