While Windows 8's Metro overhaul goes a long way towards completely reinventing the OS, in some ways it hasn't gone far enough — there are still places where the classic Windows interface resurfaces. So why hasn't Microsoft fully adopted Metro yet? Microsoft design director Steve Kaneko sat down with our own Joshua Topolsky for an interview (see the full video at the bottom), and he says that while the company is committed to Metro's design principles, there are challenges that have made the transition difficult — he says that the large Metro style interface, designed for touch interaction, doesn't scale in an obvious way to software like Office that has a lot of dense information. While Metro attempts to eliminate what Microsoft calls "chrome" (superfluous design elements), he says that chrome has traditionally served a functional purpose in crowded applications, and the design team now has to express grouping and visual hierarchy with composition, layout, font scaling, and contrast ratios.

Kaneko also shares that Microsoft is becoming a more design-oriented company, and that it's working consciously toward unifying the look and feel of its products — something that some Windows users have pined for over the years. He says that "as designers, we knew way before we actually executed that we did have a mixed message to consumers," and that the Microsoft brand was fragmented because of an inconsistent design language. Now, he says that Microsoft's design community feels more confident, and that "we're not looking over our shoulders as much as we used to." (Presumably because designers may have been wary of skeptical Microsoft executives.)

Steve Ballmer hinted at the possibility of a Metro-style version of the next Office suite back in September, but we're still not sure when, if, and to what extent Microsoft's legacy software will be upgraded with the new UI. And while Kineko says the company is certainly thinking hard about how to implement Metro, just having the vision is not enough — by his own admission, it's all about execution now.