I wouldn't take this news as the huge bummer that it looks like. One thing Microsoft doesn't have with the courier is the element of surprise. Windows phone 7 is coming out later this year, so I would think that they want to focus on that as much as possible and then consider how to scale that experience to something like a courier/tablet device.
As amazing as the concept video looked, something even better could be on the horizon.
As amazing as the concept video looked, something even better could be on the horizon.