Unfortunately, that part is just the desktop showing aspect, available from a tray icon installed by the Aero Peek app—though it likely won't be long before we see the windows previews, whether from ...

Move your mouse over a taskbar application in Windows 7, or over the outline button in the lower-right corner, and previews show up in half a second. Customize that wait time, or disable it entirely, ...

Aero and other interface enhancements that they dismiss as so much frou-frou. Guess what — there’s even more frou-frou in Windows 7, such as a new taskbar and a nice new feature called Aero Peek. … ...