Think you're missing the main point, which is that it is simple... and yet still powerful. The framework provides many features, such as callbacks (sync & async), remote classloading, auto discovery, oneway calls, etc., which is beyond the scope of many of the similar frameworks, yet IMHO is much easier to use. The other strong point of this framework is that you won't necessarily have to change your code or move to a different framework because of environment requirement changes (i.e. you start out with socket based, but have to switch to http). With remoting, is just a configuration change (which is as simple as changing the url from starting with socket:// to http://).
There are several projects within JBoss that are using JBoss Remoting since they get the previously mentioned features. One, for example, is JBoss AOP, which uses JBoss Remoting for remoting of POJOs.