An RSS feed is a very broad way of sending messages to the group. Can we add a way target messages better by specifying a 'radius' for the subscribers? This way users would only get the item alert if they are (for e.g.) within 5 miles of the positions the article refers to.
If the incoming RSS is not a geo-RSS, maybe geochat could try to associate tentative locations using GeoNames as well, but alert the user that the geocoding may not b reliable.