The Web Platform Installer (Web PI) is a simple tool that makes it very easy to download and install Microsoft's entire Web Platform in one step, including IIS, 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. Web PI 1.0 supports Windows XP, Windows 2003, Windows Vista and of course Windows 2008.
How does this concern PHP? Well, they already have versions o several popular PHP applications ready to go out of the box to install - DotNetNuke, Drupal, Gallery, Graffiti, osCommerce, PHPBB, and Wordpress with more coming all the time.
You can grab a copy of this latest release from the Web Platform Installer page on the Microsoft website.