Paul Fremantle on WSO2's registry work...
For a while I've been thinking that the SOA registry space has been a little overcomplicated...Glen Daniels was talking about this registry in the hallway at QCon a few weeks ago. Nice. You could definitely see Glen's gears turning during the sessions and discussions.
So fundamentally the approach we have taken is to build a registry/repository based on REST concepts. And as we looked at the REST space, we kept noticing how close the Atom Publishing Protocol (APP) is to our needs, so we've made that the public remote API to access the repository. Of course, if you are just browsing the registry, you only need a browser - APP is mainly there to support updating resources.
Of course, using Atom and APP gives some really nice benefits too - like being able to subscribe a feed of new resources that meet your search criteria.