Here are two things to go beyond Web Services (with ReSTfullness in mind):

• the « Web-Oriented Architecture » (WOA) concept is a lightweight version of the « Service-Oriented Architecture » concept, in a more Web 2.0 fashion.
• restlets are a Java framework for Web 2.0 applications; they replace servlets API and facilitate the composition of « mashups » or Web applications relying on information collected from other live Web applications; there even is an open source reference implementation that is about to reach maturity and is actively developped

Take-away: beyond theory (ReST), there now are concepts (WOA) and tools (restlets) for building composite Web applications without requiring SOAP, WSDL and the whole bunch of overbloated WS-* standards that come with them.