RAML does provide an integrated, free, hosted mocking service that you can deploy with a single button click in the API Designer. Once you've enabled mocking, try-it will be immediately enabled in the integrated API Console, and you can further exercise your mocked API using the baseURI inserted into your RAML file.
In addition, we will be open sourcing additional server frameworks (we already have Mule and JAX-RS frameworks) in the near future (including Node). Client generation is a bit further out, but also coming quite soon (javascript first, then others).
Disclosure: I am heavily involved with the RAML initiative, and work for MuleSoft as a Product Manager for many of the RAML tools we develop.
