agree, my point of view is just that binary xml is not the only issue with mobile terminals, there is a wider set of problems to be considered for optimizing the connection (some such as stanza acknowledgments are already there, though I don't know how many servers handle them, others such as limiting the initial roster and presence burst aren't addressed well now)
Ive been thinking on this myself and i've come to the conclusion that something along the lines of BOSH would probably be best where the mobile devices connection to the server is being proxied on the server, because for mobile devices I would have thought you'd want to be able to lock down the stuff that is sent between the mobile device and the server, things like disco and caps and whatnot you would probably want to be replied to by the proxy and never getting to the client, you would probably also want any protocols that the mobile device doesn't understand/support filtered out so they never reach the client too to reduce bandwidth waste, and of course if you are implementing a proxy specially for mobile devices you can have an nice optimized compressed wire protocol without needing to make extensive changes to the standard XMPP protocol as the proxy will just convert between them for the mobile device.
Richard
