FONGD Not to defend the seemingly invisible installation of Silverlight, but the README when you launch the installer explicitly states that it will install Silverlight: "This installer also includes a browser plug-in for Microsoft® Silverlight™, which allows you to play Smooth Streaming video content. This is installed by default. To disable its installation, click the Customize button on the Installation Type pane and uncheck the Microsoft Silverlight Plug-in option."
(Version 2.3.0.11b)