Dual-screen key feature to DS popularity

The Joplin Globe claims the dual-screen is the key feature to the DS's mass popularity and high sales volume. From the article: "The system's biggest draw, however, is undoubtedly the dual screens. As you may know, the DS flips open to reveal top and bottom screens, the bottom of which is a touch screen. The system comes with a small stylus to aid you, but your fingers work just fine for most things."

We think it's the games that directly affect the popularity. But what, in addition to the dual-screen, make an indirect impact on the system's appeal?

[via Joplin Globe]