if you are working with the Moodle 2.0 web services code, you need to know that:
1- the web service description design is going to be changed and it will not change anymore: http://docs.moodle.org/en/Development:Web_services_security#Function_discovery
2- The REST server is being developed by Ludo's Team: http://blogs.dfwikilabs.org/moodle_ws/
It will not be RESTful.
3- The XML-RPC and SOAP servers in CVS work with their respective Zend clients. They do not need our web service description design, they parse the phpdoc to know about the web service description.
4- A Java/.Net compatible SOAP server should be developed once 1) is fixed. No one is assigned to this task yet.
5- AMF server/client were not working last time I checked it, I'll have a look at it once all 1), 2) and 3) work.