The View Projects menu item displays the current Visual Studio projects for the current Glue project. Initially only one project will appear in the Projects tab when selecting View Projects. The following image shows the Projects tab with a single XNA 4 project named TownRaiser:
Synced projects are used to develop multi-platform games. For example, a single FlatRedBall project may contain a main DesktopGL project and a synced project for other platforms such as Android and Web. For more information see the Synced Projects page.