I just upgraded to a Windows 8 phone, the Nokia Lumia 521. Best feature so far is HERE Transit, part of the upgraded map and navigation suite from Nokia. I’ve had many issues with Nokia Maps in the past, but the transit feature works brilliantly.
I live in Washington, DC, and make them extensive use of the city’s excellent transit system, so any tool that makes it easier to find the right bus or train is welcome. After saving a shortcut with my address to the home screen, I now have true one-touch access to the next trip home by bus or subway. The interface is clean and logical, and includes a map showing the route to your starting point.
Well done, Nokia!