1. A computer-implemented method of communicating updates from a subject to an observer, comprising: in an observer, creating an aspect object, the aspect object comprising logic adapted selectively communicate update information from a subject to the observer based on configuration information, the configuration information comprising an attribute of the observer; attaching the aspect object to the subject; notifying the aspect object of an update; in the aspect object, interrogating the update to generate to generate the update information; and selectively communicating the update information to the observer based on a comparison between the update and the configuration information.