In what seems to be a never ending stream of leaks, elements of the Metro UI for Windows 8 have also now surfaced on the Internet. The image shows the specific style that will be included in at least one theme for Windows 8.
The image, courtesy of mswin.me, shows the back, forward, close, minimize, expand, help, and several other images that Microsoft will incorporate into, most likely, the "Aero Lite" theme that Neowin reported yesterday. This image helps to confirm that Microsoft will be using the Metro design language in Windows 8 in at least one theme, if not more.
This theme is expected to be used by users whose computers do not have the specs to run a dynamic interface. Microsoft knows that Windows 8 will be used on older hardware and wants to maintain its Metro design language across all themes that end users might use. It is not known at this time if there will be the "classic" option theme in Windows 8.