Apparently it adapts one of the most irritating features of the iPad:
The new interface offers several advantages over the traditional Windows model that will prove especially useful for touchscreen devices. As with Apple’s tablet, you won’t be able to download Metro programs from just anywhere on the Web—a change that’s certain to flummox longtime Windows users. The new interface can only run specially designed apps, which are only available through Microsoft’s built-in Windows Store. By limiting apps to those you download from a centralized store, and by strictly governing the level of access that those apps get to your computer’s resources, programs will be easier to install and malware will become less pervasive. (You can still download traditional Windows programs, though they’ll run in the Desktop view.)It's a stretch to say that imposing a Stalinist command structure over the kind of programs your computer will run is to make them easier to install and cut down on malware. Apple's operating systems are nearly invulnerable to viruses because the deep infrastructure is cadged from Unix and other open-source places, which are inherently better-built and less vulnerable to viruses. I suppose if everyone ran Linux, viruses targeting it would be more common, but surely part of the reason Apple made this choice was to deliberately cripple the functionality of the device in order to force their customers into the Apple ecosystem and thereby make a big pile of cash.