Microsoft appears to have killed the Courier concept before that two-screen device ever became a reality. It’s not clear what factors led to the decision, but on some level it’s a shame. Endgadget called it the “one of the finest unicorns that ever unicorned across our screens.” The two-screen nature of the device, while attractive in principle, may not have been as useful in real life. What was undoubtedly useful was the application suite demonstrated in their vision videos that seamlessly integrated a range of activities.
In some ways this is pure Microsoft vision, a slate-specific Office suite. Compare this with Apple’s piece-meal approach to applications. The iPad seems to have demonstrated the effectiveness of the slate as a viable device that works well as a secondary (or on occasion primary) computing device. The success is due largely to a well-executed device, a compelling interaction modality (multi-touch), and an effective marketing campaign. But the device has limitations, including poor support for free-form ink and a relatively low-power CPU.
These hardware limitations affect the range of possible applications that can be built on the platform compared to the capabilities built into the Tablet OS and now Windows 7. Microsoft’s backing off from its vision presents an opportunity for third-party developers who can devote some resources toward understanding specific vertical markets (legal, education, etc.) and designing for them. I expect that success at a few verticals will both sensitize users to the possibilities of this more natural mode of interaction and will establish a set of effective design patterns.