In a typical Apple fashion, the plug has been pulled on iOS 6 officially, meaning that whatever ways you could find to revert back will no longer work.
Source: http://www.phonearena.com/news/You-can-no-longer-downgrade-from-iOS-7-to-iOS-6_id47765
Source: http://www.phonearena.com/news/You-can-no-longer-downgrade-from-iOS-7-to-iOS-6_id47765