In building the new Windows Phone 7 Series mobile operating system Microsoft started from scratch to create a user interface which was both easy to use and visually appealing. Luke Wroblewski, the chief design architect at Yahoo!, has now done an analysis of how the interface utilises tease and transition animations to provide a better and more intuitive user experience.
LiveSide point to a post on Wroblewski's personal blog, which includes a video highlighting how the implementation of a Natural User Interface (NUI) uses content as interface controls - showing people that bits are interactive by using using "teasing" techniques. These teases encourage users to explore and touch things in an intuitive way, in Windows Phone 7 specifically by hinting at more or additional content related to the current view.
As the video points out, there is a tease on the phone's home/lock screen and also on most of the application screens where truncation - of titles and content - can persuade people to explore more of the application. Animated transitions show users that elements are active and can be interacted with, as well as giving feedback to the user based on certain actions. Take a look at the Wroblewski's blog and the video to get a better idea.