I am creating and updating some web services for use by others and many of our other applications. I've head RESTful is the way to do things now. I need to use C# for these applications, so I figured on using Visual Studio 2010. For the sake of appealing and being useful to a large user base potentially, should I make it work for both REST and SOAP? Should objects be sent and returned using JSON, XML, or let the user decide and provide all combinations. Will Visual Studio or other tools allow me to create the combinations without coding the interfaces four times? Any ideas, links to tutorials, or books to make all this as flexible as possible would be very helpful.