The new architecture allows for:

Multiple Transports
  - EA currently supports HTTP
Multiple Encodings
  - EA supports XML as text.
  - The next EA will include MTOM/XOP and Fast Infoset
Multiple Protocols
  - EA supports SOAP 1.1
  - The next EA will include SOAP 1.2

The next EA due out before JavaOne will also have a dynamic runtime. This means no more stubs/ties, serializers, deserializers etc. All artifacts generated by the JAX-RPC SI will be 100% portable to other JAX-RPC 2.0 implementations. I will blog about this again when the next release is available.

Arun Gupta has blogged about how the current JAX-RPC 2.0 EA can be deployed ontop of JWSDP 1.5. You can read his blog at: JAX-RPC 2.0 EA on JWSDP 1.5

You can dowload the current EA at: here.