Anyone who has Kinect for the Xbox has probably seen the Video Kinect feature. It allows you to video chat with your friends and family on your television screen using Kinect with a Windows Live account. The problem is that there aren't a whole lot of people using it. When I searched for friends using Video Kinect, I found just two - a nephew of mine and an old friend who has moved back the the US.
Microsoft's recent purchase of Skype will likely bring a Video Kinect type of service to the Xbox but with access to Skype's userbase of over 600 million registered users. This will make it possible to contact many of your friends and family, either directly through Skype (currently free) or calling their phone (a paid service). What are the chances you are going to find grandma using Video Kinect? It is unlikely that you are going to find her on Windows Live (unless you have a pretty hip grandma).
Skype in the classroom
Skype Education already lets you use Skype in the classroom to connect with other classes and experts from around the world. Wouldn't it be exciting to be able to use the Kinect technology as well where you can use hand gestures to operate the device and share and discuss content on the screen with each other?