I'm going to disagree.
I'm a reporter to reporters, and in that role, I've recently reviewed AT&T Navigator (aka TeleNav 5.5), MapQuest Navigator, Garmin Mobile and several other offerings. With the single possible exception of display size, I think these BB navigators outperform dashboard units.
And a fundamental reason for that is that they don't deal with static maps.
Each one gets up-to-the-minute server-based maps for the entire planned trip corridor when travel begins, so the maps are in the handset regardless of whether or not there's any cell signal. Each one updates regularly to fetch new info about road conditions, traffic jams, etc. And the scheme is extremely reasonable in terms of a conservative amount of total data traffic making everything happen.
I also tried VZ Navigator when it was new and I hated it. With it, lose a signal and you'd lose your way. Track your path and you can't make or take calls. And there were 4-5 ways they upped your bill for using it.
This is not to undermine the importance of your discovery of these programming options - only to address that I strongly believe that stored maps are ultimately a less than optimal choice for navigation.
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