According to Nokia, they are making use of the pureview technology. It won’t be the 42 megapixel, but “only” 12 megapixel.
http://www.nokia.com/global/products/phone/lumia920/specifications/
Your link says 8.7 MP sensor, not 12. Nokia came out and said that their use of the term pure view technology is not really associated with any specific technology, just any system they make that gives good results.
If that doesn’t make sense to you, join the club.