Before you make any decisions, be aware that HTTP/REST support in WCF is in the process of changing significantly. See http://wcf.codeplex.com/. There will be a large amount of backwards compatibility but the new library is a complete re-write from the perspective of HTTP and WCF.
Also be aware that OData, although useful for a specific subset of applications, is not a general purpose REST framework.
If you need something .net, now, and you really want to do REST right, look at OpenRasta. If you only want to do REST because it has good marketing buzz then ASP.NET MVC will probably be good enough for you. If you are just in experimental stages then I'd keep watching the new WCF libraries.
