Mozilla is set to release Firefox 26 for Windows 8, complete with a Metro/Modern interface, this coming December. If development continues as planned, the Metro/Modern version of Firefox will have taken a little over an entire year to be released when compared to Windows 8's release in October of 2012.
Mozilla will release Firefox 26, which comes with the Metro/modern interface, on December 10th. Mozilla will also roll out an Aurora build and Beta build of Firefox 26 on September 16th and October 28th respectively.
Firefox for Windows 8 will include a new Metro style Start Page, support for Firefox Sync, Metro touch and swipe gestures, integration with Windows 8 “charms”, and a new interface. For now, Firefox for Windows 8 will not work on Windows RT and will require Windows 8.