In the trunk, we've made events.triggerEvent take an arbitrary number of arguments to be passed to the listeners - in addition to the event object. For non-browser events, this event object has references to the "object" (events.object) and "element" (events.element). Instead of tacking on additional positional parameters, it makes sense to add on additional event related information as properties of this event object.
In addition, we often call events.register and events.unregister multiple times sequentially with the same scope (object argument). This can be made a bit more convenient by introducing events.on and events.un methods. These convenience methods are similar to those on observables in Ext, only supporting the case with a common scope right now.
