Microsoft's "Ribbon" graphical user interface, first introduced with Office 2007, was a dramatic departure from its straightforward menus of yore.  It offered users quicker access to more options and more visual cues.  But for some, it also brought more distraction and headaches.  

For better or worse, the Ribbon has migrated to Window 7's Paint tool, to the WordPad app, and to Microsoft Live essentials.

Now Microsoft is preparing to take a bold next step, adding the ribbon to arguably its most integral part of Windows -- the Windows Explorer.

According to iconic Windows bloggers Paul Thurrott and Rafael Rivera an early build of Microsoft's upcoming Windows 8 operating system sports a partially finished Ribbon design driving menus within Windows Explorer.  They show off screen shots of the design in action.  
Mr. Thurrott and his colleague seem less than thrilled about the idea.  They write:

In early builds of Windows 8, this Ribbon UI is only half-finished and, frankly, of dubious value. In fact, based on the divergent ways in which various related UI elements are repeated around the window frame, we get the idea that the use of the Ribbon in Explorer is, in fact, quite controversial inside the halls of Microsoft’s Redmond campus.

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In the current pre-release builds we’ve seen, the Ribbon is a serious work in progress and is quite unattractive. It’s unclear whether Microsoft intends to move forward with this UI as-is, or whether it will appear only in certain UI types. Based on what we’re seeing, however, it does seem that there will at least be a toggle to disable this top-heavy UI. So if you don’t like the Ribbon in Windows Explorer, hopefully you’ll be able to turn it off.

It's possible that Microsoft will give users an option to switch back to a Aero Lite (formerly "Aero Basic") theme, similar to Windows 7's, restoring the traditional menu.  It is also suspected that Microsoft may pack in a third user interface option -- its tile-based Metro UI found in Windows Phone 7.

Windows 8 is rumored to ship in 2012 by numerous sources.  If accurate, this means that the final UI content of Windows 8 may be partially dictated by what there's time to finish.  Also whether or not Microsoft must weigh the benefits of packing in three distinct menu UI styles, versus the confusion that might cause.

Even if users are given the ability to switch back to a non-Ribbonized Explorer, they may be prohibited to do so in some corporate settings, due to their local IT department's restrictions on changing control panel settings.  Thus some veteran users may find themselves forced to use the Ribbon -- at work at least.

It's a undeniable fact that Office 2007's Ribbon was much maligned.  One of the more levelheaded analyses of the feature was given by one of our readers in a past piece.  They argued that much of the criticism was from people unwilling to relearn a new interface.  They stated that the best test of whether or not the ribbon is a good idea is how new users (e.g. young students) react to it.  

This seems pretty apt.  If new users can use the ribbon to accomplish tasks with greater efficiency than their plain-menu-equipped predecessors, Microsoft's strategy is vindicated no matter how much criticism is leveled against it by veteran users.  But if it turns out the graphically rich interface simply is less efficient for everyone, which is clearly a problem.

In short the Ribbon design is a high-risk, high-reward scenario.  Microsoft will be chastised if it doesn't innovate.  And it will invariably be chastised if it does.  The Windows Team will just have to make their best judgment call, no matter what the blogosphere thinks.