I just purchased OnCourse Navigator 8 - OCN8. It is the iGO8 software repackaged for the US market:
http://www.navngo.com/
I first saw this in action in a taxi cab in Budapest in October, and asked the driver what he was using since it was running on a HP PDA.
NavNGo is based in Budapest, but have maps for all over the world.
It has a few "quirks" running on a 64MB X51v running WM6.1, but the graphics, useability and features are great. Seeing 3D buildings on screen as you pass them (in certain cities) is pretty amazing.
I just got back from a trip from Atlanta to Florida, and I switched back and forth between iG3 and OCN8. And, liked OCN8 much more.
Please ask if you have any questions.
Rob