Microsoft will walk away from the "Metro" tag it's been using for over a year to describe the new environment and apps in both Windows 8 and Windows RT, the company confirmed Friday.

"We have used Metro style as a code name during the product development cycle across many of our product lines," a spokeswoman said in an emailed statement. "As we get closer to launch and transition from industry dialog to a broad consumer dialog we will use our commercial names."

Late Thursday, The Verge reported it had seen a Microsoft internal memo that explained to employees the change was a result of "discussions with an important European partner" that forced Microsoft to "discontinue the use" of the Metro brand.

A replacement for Metro will be introduced this week, the memo continued, which hints at a renaming by today or Saturday. Until then, Microsoft employees are to use the phrase "Windows 8 style UI."

Also yesterday, reports on the Web said Microsoft had sent a similar missive to third-party developers.

"This isn't a huge deal for Microsoft, more of an embarrassment, but it is an unneeded distraction to what they need to be getting done," argued Patrick Moorhead, principal analyst with Moor Insights & Strategy, in an email today. "One of the first rules I learned as a junior product manager was to only apply non-trademarked names to my products."

Microsoft has been using the word "Metro" to define a wide range of components in Windows 8 and Windows RT, including the underlying design philosophy that relies heavily on topography; the new minimalist, tile-based apps; the environment they run in -- one of two in Windows 8, for example -- and the flattened, color-subdued user interface (UI) for traditional Windows programs and services, including the upcoming Office 2013 and the just-launched-in-preview Outlook.com free email service.

As of Friday, the supposed placeholder phrase of "Windows 8 style UI" could not be found by searching Microsoft's website, although use of "Metro" and "Metro style" was rampant.

If the plan all along was to use Metro as simply a code name, Microsoft did a poor job of communicating that to developers, users and the press.

When Stephen Sinofsky, the head of Microsoft's Windows and Windows Live Division, first posted about the new UI in the "Building Windows 8" on Aug. 31, he used "Metro" 14 times alone or as an adjective such as in "Metro style," "Metro experience," and "Metro world." Sinofsky never mentioned that Metro was a code name, or enclosed it in quotation marks to mark it as a possible placeholder.

And that was a major mistake, said Moorhead.

"I believe it will take years to leach 'Metro' out of the industry nomenclature," Moorhead said.

Several reports named Metro AG, a Dusseldorf, Germany-based conglomerate that's the world's fifth-largest retailer, as the origin of the complaints that led Microsoft to dump Metro.

A Metro AG spokesman declined to comment, saying, "we generally do not comment on market rumours."

Microsoft said that the change was not the result of litigation, but declined to answer a follow-up question whether Metro's departure was due to simply the threat of litigation, perhaps related to trademark or copyright issues.

The Microsoft spokeswoman also declined to name the "important Microsoft partner" mentioned in the internal memo cited by The Verge.

Dropping Metro as a brand will let Microsoft play to its strength -- the Windows brand -- said Moorhead. "Any effort or dollars invested in the Metro brand is taken away from the Windows brand," he said. "Fortunately for Microsoft, they build awareness, familiarity, and in some cases even preference for a 'Windows UI.'"

But that brand value will be lost, Moorhead claimed, because of the likelihood that "Metro" will be hard to kill.

Microsoft has its work cut out for it: On Wednesday, it announced Windows 8 had reached the RTM (release to manufacturing) milestone, with copies reaching developers, IT professionals and corporations in less than two weeks.

Windows 8 goes on sale, as do Windows 8- and Windows RT-powered PCs and tablets, on Oct. 26.

Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed . His email address is gkeizer@computerworld.com.

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