Microsoft has uploaded the source code for MVC 3 Preview 1. You can download the source code from below
http://www.microsoft.com/downloads/details.aspx?FamilyID=cb42f741-8fb1-4f43-a5fa-812096f8d1e8&displaylang=en
You can download the preview 1 from below link
http://www.microsoft.com/downloads/details.aspx?FamilyID=cb42f741-8fb1-4f43-a5fa-812096f8d1e8&displaylang=en
There are some useful features (considered to be included in MVC 3) is now available in MVC Preview 1.
Some of the features in preview 3 features are below
- New ActionResults
- New Razor View Engine
- HttpNotFoundResult, HttpRedirectResult with support for Permanent Redirects, and HttpStatusCodeResult.
- Global Filters
- Model Binding to JSON
- Validation – .NET 4 introduced IValidatableObject and improvements on ValidationAttribute to provide even better validation and ASP.NET MVC 3 will offer better support for them.
- Dependency Injection and Common Service Locator Enhancements
You can find more information
http://weblogs.asp.net/scottgu/archive/2008/05/27/asp-net-mvc-preview-3-release.aspx
http://haacked.com/archive/2010/07/27/aspnetmvc3-preview1-released.aspx
It is very early stage so there are no guarantees that all these features will be included in the final release.