Advantages of REST-over-RFC approach?

Hello,

I've read the SAP NetWeaver How-To Guide: SDK for the ABAP Development Tools and I think I understand how the entire chain of communication is supposed to work. I can also see some benefits of using this approach for setting up an entirely new link between applications where no previous interface existed. However, I'm not sure about use cases where a well-established set of RFC function modules already exists. Is there any advantage (other than having a clean architectural conscience :-)) of using the REST approach over using traditional RFC calls?

Thanks

  Volker