Windows Vista and XP had basically the same interface and while it worked, it was boring and you probably had to change the visual settings on your computer to make things work. It seemed that with 7 Microsoft took some ideas from the Apple's design but made things more confusing adding a Dock at the bottom of the screen but keeping shortcuts.
In Windows 8 they made everything more streamlined while keeping it functional and intuitive without making it seem like another Apple copycat. I was at first disappointed with how you couldn't customize the interface too much but realized that it was this reason that Apple's design is effective: it forces developers to fall into their design guidelines. The "tiles" are a lot like apps you would find on any Apple product. Their "Metro" leaves a lot of room for creativity for developers using their platform while maintaining the much needed simplicity of their new user interface.
Check the link for more info http://www.fastcodesign.com/1670705/microsoft-new-design-strategy#1