I don't work there, but I doubt it. With rendr, both the client- and server-side portions of the Backbone stack still need to consume an upstream API. If I had to guess, I'd say that for projects they're building that use this stack, all the templating/rendering/presentation logic is in JS, but that the database interaction stuff probably isn't; they probably have Rails apps that expose a RESTful API that the rendr apps consume.
This is exactly right. We still have 5 years worth of business logic in Rails, so we just expose a RESTful API as part of the Rails app. The same API is consumed by our iOS, Android, Mobile Web, and Desktop clients.
Great thanks I'll take a look at it again, I seen the "Interacting with a RESTful API" section in the wiki left blank and assumed it was in the pipeline.