Description Set Profiles

I'm currently working on Dublin Core Description Profiles. The hope is to have a machine-readable constraint language for the DCMI Abstract Model - this is something currently lacking in the DCMI taskgroups. At the same time, there's discussion about what Application Profiles are really intended to convey. Are they just recommendations or can they be seen as constraints on a Description Set (DCAM terminology). The current thinking is that they are actually constraints and that recommendations belong in other forms of documentation. Alistair got really excited about the notion of constraint languages for graph metadata - see his post for details. Expect interesting results coming out of this work. Oh, and Alistair - drop the "Son of DC" name before the DC community hears about it :-)