I have implemented such a functionality for real time monitoring using gevent and works extremely well. This HTML5 feature is supported in recent versions of Chrome, Opera, and Safari and in the beta versions of Firefox, but not in any version of IE: http://caniuse.com/#feat=eventsource
Thanks for the links. I wasn't aware that server sent events existed. It looks cool, but is just another thing that can't be used because of compatibility yet :(.