This is actually one of the things that could keep me from moving to the Android platform in the near future. I agree that the future of Windows mobile is not looking too bright, but I have a considerable investment in software for Windows mobile
I was looking at the iGo, but they only ship it on memory cards preinstalled. And it is not exactly like they use the 16gb memory cards either. If there is a way to move the software to a larger memory card I would definitely consider it. I personally use iGo for European maps which is sold as a program which is then installed on the memory card.