[pmontra]

Not all actor based languages can broadcast messages to e every actor. Example: Erlang sends messages to a given process. To broadcast to many processes you must know the pids of all of them. Or send to a "bus" process that knows the pids of every one else. Performance bonus (maybe) if the bus knows which process will be interested in a given message. Not much different than having a central registry of objects acting as a bus and dispatching method calls. Furthermore you can have tight coupling with message passing too.