Mary Jo Foley, writing on ZDNet, notes that the official terminology being used in to refer to the design style previously known as Metro is Microsoft Design Language. Microsoft had previously quietly killed off the Metro name, and although an explicit reason was never cited, the common assumption was that it was related to trademark overlap with German retail giant Metro AG.

Metro, now Microsoft Design Language, covers the typography, iconography, tiled interfaces, and more. It was introduced with Zune devices, and has since been applied and developed in Windows Phone and Windows 8. Microsoft has heavily evangelised a design-led message to developers and press (e.g. see our coverage of Nokia's World 2011 here and here).

From ZDNet:

The biggest revelation I've seen from the newly published information so far is that Microsoft officials are now using "Microsoft Design Language" as the newest way to refer to the design language and tiled style formerly known as "Metro."

I had a number of my Twitter chums tell me in the past couple of weeks that Microsoft was now using "Microsoft Design Language" as the replacement for Metro, but a Microsoft spokesperson would not confirm, when I asked, that this was the official new lingo... I guess Microsoft's use of it on the Build 2012 site is as close as we'll get to an "official" confirmation.

As Ewan noted in an earlier editorial there's a certain attachment to the Metro terminology, but ultimately what matters is creating intuitive user experiences.

Okay, everyone who writes about Microsoft is going to have to tread carefully and not automatically type Metro into their articles, and I'm sure us geeks will put a huge spotlight on this issue, but we're not the market that Microsoft is addressing or selling to; we're going to buy these devices, even if they do have a silly name. Microsoft need to deliver a clear message, a simple message, an understandable and focused message to the public. Losing the name Metro gives them another reason to simplify the Windows 8 story they need to sell during the rest of 2012 and into 2013. Like Chris Froome in the Tour De France, it's time for Metro to peel away and let the rush of Windows 8 devices take the glory.