The asp.net MVC 2 RC 2 was made available on February 4, 2010, you can download it here.

This new release has some cool features such as the following:

Areas:
The Areas were first introduced with the MVC 2 Preview 1 release. However, I've decided to include some information about areas since the ASP.NET team has made some changes to this feature since its release.
Areas allow developers to partition large projects into smaller more manageable smaller units that are referenced to as areas. Each area has the same structure as an asp.net MVC project, and within an application you can have many of these MVC structures called areas. This new feature helps manage the complexity when dealing with large projects and facilitates multiple teams working together in separate areas of an application.



After you add an Area, Visual Studio will create a folder labeled Areas and within this folder you'll have your new RSVPS area with the necessary folder structure that allows you to separate the files and the functionality of an specific area of your application:




Model Validation:
This new release uses Model validation instead of Input validation as the previous versions did. This means that now MVC runs all validators on an object, as long as that object has at least one value bound into it during model binding. It also uses Data Annotation for validation which allows you to add validation rules declaratively to Model and ViewModel classes within an application.



Read Brad Wilson's blog for details about this change.

The above are some of the new features that I really like and use with ASP.NET MVC 2 RC2. If you want to upgrade your existing MVC 1 projects to MVC 2 RC2 you'll need to do the following:


Upgrading an ASP.NET MVC 1.0 Project to ASP.NET MVC 2 (as described in the ASP.NET MVC 2 RC2 Release Notes)

To upgrade an existing ASP.NET MVC 1.0 application to version 2, follow these steps:
1.    Make a backup of the existing project.

2.    Open the project file in a text editor (the file with the .csproj or .vbproj file extension) and find the ProjectTypeGuid element. As the value of that element, replace the GUID {603c0e0b-db56-11dc-be95-000d561079b0} with {F85E285D-A4E0-4152-9332-AB1D724D3325}.
When you are done, the value of that element should be as follows:
<ProjectTypeGuids>{F85E285D-A4E0-4152-9332-AB1D724D3325};{349c5851-65df-11da-9384-00065b846f21};{fae04ec0-301f-11d3-bf4b-00c04f79efbc}</ProjectTypeGuids>

3.     In the Web application root folder, edit the Web.config file. Search for System.Web.Mvc, Version=1.0.0.0 and replace all instances with System.Web.Mvc, Version=2.0.0.0.

4.    Repeat the previous step for the Web.config file located in the Views folder.

5.    Open the project using Visual Studio, and in Solution Explorer, expand the References node. Delete the reference to System.Web.Mvc (which points to the version 1.0 assembly). Add a reference to System.Web.Mvc (v2.0.0.0).

6.    Add the following bindingRedirect element to the Web.config file in the application root under the configuraton section:



7.    Create a new ASP.NET MVC 2 application. Copy the files from the Scripts folder of the new application into the Scripts folder of the existing application.

8.    Compile the application and run it. If any errors occur, refer to the Breaking Changes section of this document for possible solutions.

The above instructions are from the Release Notes document included in ASP.NET MVC 2 RC2.

Good Luck!