Microsoft has released the release candidate of Microsoft Web Platform Installer

The Web Platform Installer (Web PI) is a simple tool that installs Microsoft's entire Web Platform, including IIS7, Visual Web Developer 2008 Express Edition, SQL Server 2008 Express Edition and the .NET Framework. Using the Web Platform Installer’s user interface, you can choose to install either specific products or the entire Microsoft Web Platform onto your computer. The Web PI also helps keep your products up to date by always offering the latest additions to the Web Platform.

New Updates! Now supporting Windows XP and Windows Server 2003, Web PI makes it easy to install and stay up-to-date with the Microsoft Web Platform. This updated release lets you install ASP.NET MVC, Visual Studio Tools for Silverlight, and much more!

System requirements
Supported Operating Systems are: Windows Vista RTM, Windows Vista SP1, Windows XP, Windows Server 2003, Windows Server 2008
You must have administrator privileges on your computer to run Web Platform Installer
.NET 2.0 Framework
Supported Architectures: x86 and 64-bit

Microsoft Web Platform Installer (Release Candidate)