Here's a statement from Nokia.
"Today Microsoft has announced the key new ingredients of the latest 'Mango' release of the Windows Phone operating system. This is the software that will be used on the first Nokia with Windows Phone device, and so should be of keen interest to Nokia-watchers everywhere."
During the Mango keynote, Microsoft revealed that they already have Nokia devices running Mango in their labs. Microsoft and Nokia still love each other. Awww~ ♥