If an user changes its buddy icon while you are connected, the change is not forwarded to empathy. But if you disconnect and reconnect you will get the new avatar
This could be related to #23647. Please provide debug logs for Gabble, as described on the wiki: http://telepathy.freedesktop.org/wiki/Debugging
I believe this is fixed in 0.8.5: if the server tells us it's too busy to give us a vCard just now — which Google's server often does — we now try again later. If the problem doesn't go away with 0.8.5, please re-open this bug with the requested debugging output.
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