I have a small association with deegree acting as their mentor during OSGeo incubation. Indeed deegree is the only project taking part that sports the OSGeo stamp of approval.
In this case indicating the project has their open source license story in order and follow an open development process.
The recently released deegree 3 supports WPS giving them an opportunity to participate in this years shootout. I was able to catch up with Markus Schneider and ask him the same questions covered in the panel discussion.