That's not what he said, he said the notification was by "Instant Message", not that the notification was "instant".<p>Obviously it have to poll the page, but in principle that can be polite, ideally it'll have a decay feature where if it hasn't been updated in a while the checks will by steps decay to, say, once a day, then once a week, then once a month, and give up after, say, 5 years.