RS232 is actually sort of a standard that crosses over from the pro audio and pro video industries to the high end home automation industry. Manufacturers such as Crown have developed sophisticated systems that utilize the protocol. (Crown IQ for instance) Many other manufacturers have also adopted this protocol in their flagship products. BIamp systesm, DBX, the list goes on. Crestron and AMX enjoy a healthy market share because they can interface via RS232 with many of these other systems as the graphical control interface. As NLM pointed out, the increased sophistication and flexibility is the real benefit. However, with greater flexibility and complexity comes a steeper learning curve.