As part of our oncology solution, we had to build mobile applications. All our services were built based on SOAP. For our web application SOAP/WS-* worked out very well. But, when it comes to mobile world, SOAP was too heavy. Performance on our iOS application was so bad with SOAP that we had to implement part of our server solution to support REST. At that time there was so much confusion on which Microsoft technology to be used to build RESTful services.
Recently Microsoft released ASP.NET MVC 4.0 Beta (with go live license). If you are a Microsoft shop and want to build RESTful web APIs, look no further, just download MVC 4.0 beta and use it.
This gives you all the infrastructure you had in the MVC world and world class support for building 100% HTTP compliant web APIs.
Implement authentication and logging as cross cutting concerns (using delegating handler a.k.a message handlers in the HTTP pipeline). I will try to post some code snippets on these topics soon.
Once you start building web APIs, the following tools are MUST have:
1. Firefox’s REST plugin (you can send GET/POST/PUT requests)
2. Fiddler (you can send GET/POST/PUT requests. If you have a secure/https server while testing, FIREFOX plugin did not work). Fiddler has much better XML/JSON viewing (of your responses).