There are several changes in Preview 3 we need to know about, because there is a reason why your old code don’t want to compile 
1. The “FilterExecutingContext” (using in the OnActionExecuted method) and “FilterExecutedContext” (using in the OnActionExecuting method) are now called “ActionExecutingContext”/”ActionExecudedContext”.
2. RenderView is now only available from ComponentController class, not from Controller class.
More about Using an ActionFilter.
June 2, 2008 at 3:20 pm
Nikita,
when will we see release? Do you have such information? Ask MS gurus pls
June 3, 2008 at 3:52 am
He he eh… They even in trouble to help us with Windows Server 2008 volume license activation… Only hope that some ASP.NET relates thing will be released are Scott(s) – Gu and Hanselman… But, base on their latest comments we will see at least several previews more before RC.