I really do not understand what the holdup is. I had a Windows Mobile device years ago that had GPS and on device maps. My BlackBerry has tons of free space on its MicroSD card just waiting for maps. It just blows my mind that my sub-$100 Mio c310x is a better GPS than my $400+ BlackBerry Bold. Both of them have similar components minus the touch screen with the Bold trumping with a faster processor and more memory!
So why am I still waiting for TeleNav, Google Maps, or BlackBerry Maps to refresh the maps on my device? Is it impossible to even cache the maps locally? The only reason I think this is not happening is because carriers are afraid of losing their $10/month navigation plans. This could easily be solved by offering a $50 one time GPS package that did not download information from the wireless network and then paying a optional monthly fee to keep the maps updated. Then at least I would not have to wait 10 seconds for my BlackBerry to download every turn… Or lose my GPS every time I go out of cell signal. It would also free up bandwidth on the carriers network.
So what do you think? Are you interested in on device maps?