Diffserv service classes

In the continuing effort to make Diffserv useful on the Internet, the Transport Area working group has the draft: http://ietfreport.isoc.org/idref/draft-baker-diffserv-basic-classes/ The draft has a little bit for everyone. Lots of rope/flexibility for application developers. But have any network operators thought how they could actually support the framework in any meaningful way? And assuming the network actually supported it, what happens when you throw such fine grain differentiated traffic at the network?