Windows 8 revealed, don't take it as a flag but it's a four-paned window echoed from Microsoft's new Metro design.
[img]http://dl.dropbox.com/u/57456927/forum/Feb2012/win8logo%20%281%29.png[/img]
Windows previous versions and logos:
[img]http://dl.dropbox.com/u/57456927/forum/Feb2012/win8logo%20%282%29.png[/img]
Windows 8 Logo Revealed
From the OneCebu archive, last updated February 10, 2014. Some details may have changed.