Even with DRM people still pirate software (but false perceptions I guess). Not to mention if they were smart they could just make you pay for navigation so even if their maps and all got pirated, it wouldn't be useful unless you paid whomever for directions and navigation. But oh well. =P

Then there's the issue I don't think DRM is coming to Maemo 6 (and its unknown whether the n900 will be upgradable to Maemo 6)

I don't see Garmin porting their software to other devices, have they even ported it to the iPhone? I could see companies like TomTom who have been more open about it if the n900 is popular enough.