Users are creating content, they are creating instant mashup application, they are using the social networks in the open and API’d world. You can now see loads of information on the user screen than it was in the past. The user interfaces also needs to evolve rapidly adjusting to this information overload and ReadWriteWeb has some interesting examples of such user interfaces. When you think of user interfaces don’t just think of computer screens and keyboard and mouse based user controls. If you look at the touch based mobile interfaces and motion based wii controls, they are just the start and the future has lot many more interesting need and usage of human computer interactions like giant screens, shadows play, thought control, virtual environment and many more. Related stuff: Richard Ziade points to iPhone Human Interface Guidelines for Web Applications Smashing Magazine had done a similar coverage in the past and talks about gaming, reaction and touch based UX. Jess3 is right ATM machines are boring 
Via Billy Hylton Julia Hanna’s HBS Working Knowledge article, “Radical Design, Radical Results”
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It sounds like some instances of the user experience are migrating to the users themselves who are authoring content.