Phil Hunt has this interesting demo of the CARML-enabled attribute service API in for the IGF Attribute Service. Personally I would have preferred a downloadable sample application to a video, but it’s still interesting. The OpenLiberty folks seem to be the right track by focusing on keeping the developer interface simple to use.
Of course this is only useful to the Java side of the application development spectrum. It will be interesting to see if there is ever any traction on developing .NET and scripting language bindings for this.