Great presentation but I wonder if you could help steer me. I need to write an application to offer interoperability to our customer for which I was going to use WCF services. However, this functionality is not required imminently and is dependant on their own development progress. In the meantime I will use the same method calls for internal applications.
I really like the look of RIA Services but if I wrote my internal applications with RIA Services could I then offer the interoperability that I require. For example, in your demo presume that you want to expose the GetBooks method to a customer who wishes to write their own application to fetch the data. How easy would it be?