CHI 2008 proceedings
Virpi Roto, Pekka Ketola and Susan Huotari presented a paper describing user experience evaluation at Nokia at the recent CHI 2008 conference:

Abstract
Nokia has a long history in designing for experiences, as mobile phones are very personal and experiental devices. We have established processes to take user needs and wants into account when designing new concepts, and we do various types of evaluations with real users during the development process. Experience evaluations are, however, an area we want to improve. In this paper, we describe the user experience evaluation practices in the different phases of Nokia product development process.

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