Came across this today, Donut Output Caching in ASP.NET MVC 3. This project seems to solve all of the problems that you would encounter with ASP.NET built in OutputCache if you attempted to use it with MVC3. The builtin output cache is very unhelpful for real world MVC applications.
PM> Install-Package MvcDonutCaching
BloggingContext.ApplicationInstance.CompleteRequest();
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