How do interface Windows 8 UI and usability experts rate all the changes?

When Windows 8 debuts on October 26, users will be confronted with the most radical changes to the look and feel of Windows in nearly 20 years. The traditional desktop has been relegated to second-class status, hidden beneath Windows 8's new touch-centric Start screen. And that’s just the first confusing surprise that awaits long-time Windows users.
Traditional point-and-click functionality on the Windows desktop will also change, to accommodate the needs of the new touch-centric interface. Once they get past the new Start screen and enter the traditional desktop interface, users will discover that the Start button is gone, and that key features such as the Control Panel and Search have moved to the new Charms bar, which pops from the right side of their display.

The new Start screen—with the Charms bar exposed on the right edge.

Microsoft is changing the design of Windows to adapt the OS to our new multidevice world. So whether you're playing Diablo III on a desktop PC, checking quarterly numbers on an Ultrabook, or reading an ebook on a tablet, Windows 8 can serve as the operating system in each hardware scenario.
“[With Windows 8] Microsoft is doing something we are all going to have to do soon, which is designing for all these different outputs and inputs,” says Josh Clark, an interface designer and the author of Tapworthy: Designing Great iPhone Apps.
But Microsoft's new direction poses a problem for users: Many people who’ve played with the RTM version of Windows 8 on non-touch-enabled desktop PCs complain that the new OS is difficult to use.
“The problem for Microsoft is that it has millions of users who've been using their products for a really long time,” says Jared Spool, a usability researcher with 30 years of experience, who is the founder of usability training and consultancy firm User Interface Engineering. Spool says that the question facing millions of longtime Windows users is, How much downtime are they willing to endure in order to learn about new features that may or may not be useful to them?

The longtime user dilemma

It’s too early to say how people will respond to tablets running Windows 8, since the devices haven’t shipped yet, but PCWorld’s initial experiences have been positive.
Early adopters using traditional mouse-and-keyboard PCs, however, have experimented with two public Windows 8 beta versions of the OS since early 2012; and their reaction, while far from unanimous, has tended to be negative.
Raluca Budiu, a user experience specialist for usability consultancy firm Nielsen Norman Group, has been running user experience tests with the Windows 8 preview releases to see how people deal with the new interface changes. Budiu says that users generally experience several pain points in Windows 8, most notably hunting around for traditional functionality that’s now hidden in pop-up sidebars.
For example, to scroll through recently used apps on a Windows 8 touchscreen tablet, you simply use a swiping motion with your finger. But on a desktop PC, you must hover your mouse cursor in the lower-left corner of your display, and then move up to see a sidebar with thumbnail listings of recently used apps. This is a fairly difficult technique to master, according to Budiu.

When navigating the new Start screen with a desktop mouse, if you want to see a thumbnail listing of recently used apps, you must hover the wee cursor in the lower-left corner.

Budiu shared with PCWorld a number of other pain points from her study with Windows 8 keyboard-and-mouse users. Here are some of them:

• “So far, in our testing, discovering and remembering the different gestures was a big issue, because these gestures lack affordance and people just don’t click randomly on the screen hoping for something to happen.”
• “Also, reliably reproducing those gestures was difficult for some users. Closing windows and starting all over, which a lot of people tend to do when something is not right—for instance, when an app gets stuck—was also very difficult.”
• “Some mouse gestures are really hard to replicate. For instance, we’ve seen users struggling to expose the right-hand-side charms by hovering on different sub-regions of the right edge, rather than on the upper or lower corner.”
• “The right button of the mouse is used to expose controls or text fields throughout the interface. Right-clicking is a fairly expert user behavior, and in our testing, some users never did it.”

Clearly, navigating the desktop isn’t immediately intuitive in Windows 8. Newer PCs will try to simplify the task of accessing hidden menus by introducing multitouch-enabled mice and touchpads that support tablet-style gestures on a PC. But even so, users will have to learn new ways of interacting with Windows.

'Dualing' Windows

Learning how to navigate one system is hard enough, but on Windows 8 you have, in effect, two different and somewhat separate operating systems: the old Windows desktop and the new touch-friendly start screen. You might be able to get away with spending most of your time in the interface you prefer, but sometimes you’ll have to navigate both of them.
Working with two interfaces also means having to associate different apps with different UIs. Want to read a Kindle book? You can download Amazon’s app to your desktop or to the new modern UI, or both. Want to watch a Flash video in your browser? Use Internet Explorer for the desktop, but not the version for the Windows 8 UI.

This is how Internet Explorer looks when it's launched from the Start screen. Notice the lack of 'chrome'—buttons, scroll bars, and similar types of window dressing.

Each interface also has its own rules for interaction and navigation, such as vertical scrolling for the traditional desktop, and horizontal movements for the new Windows 8 UI.
“Multiple ways of doing the same thing usually make it harder for people to learn how to do it,” says Budiu. “My guess is that in the long term, most people will stick to just one version [of an app]—for instance, use IE only in the desktop environment.”
Other experts are more bullish on the dual nature of Windows 8. “Switching back and forth between the two interfaces may confuse some users, as they need to keep track of which application runs in which context,” says Michelle Li, a senior user experience designer for Deloitte Digital. “Over time, however, users will adapt.”
Microsoft has  added some guidance for users to alleviate the pain of switching between the two interfaces. Internet Explorer, for example, will offer to move you to the desktop version if you encounter against something it can’t display in the Windows 8 UI.
But why take this dual-OS approach at all? Wouldn't users be better off if each UI were matched as a stand-alone product to a particular device type?
On a 7- or 10-inch tablet, for instance, the Start screen makes sense, because excess desktop-style “chrome” elements (menus, windows, and buttons) would leave little room for content. Tablets lend themselves to full-screen experiences, so having menus appear and disappear with a few taps makes sense here.
On desktop PCs, however, hiding menus and controls is less efficient. Desktop displays afford plenty of screen real estate to showcase secondary windows and buttons that we find convenient for so many productivity tasks in Office, Photoshop, and other programs. ”Every hidden control [on the desktop] means an extra action needed to expose that button,” Budiu says. “For the desktop, that interaction cost does not justify the benefit. Hiding controls just doesn't give you that much extra screen space.”

Touching the future

So where is Microsoft headed with Windows 8, the unitary OS designed for desktops, all-in-ones, notebooks, Ultrabooks, and tablets? Could Windows 8's modern UI completely replace the storied desktop one day?
No one knows for sure, but after spending time with Windows 8, I can’t help feeling that this is the first step in a much longer interface design journey.
“I think that this is a transitional period from old-school Windows into whatever it will turn into,” says Clark. “Right now we're seeing a fair amount of compromises to accommodate a variety of inputs, form factors, and also older software. As with anything that's a compromise, it's going to feel a little bit clunky. But design is full of compromises.”
Sometime after October 26, we should see whether those design compromises pay off for Microsoft and the future of Windows.