I hope that everyone using a GPS unit is keeping it up to date w/ current maps.
I know on my TomTom, that there is a thing called "MapShare" where users make reports to changes in the roads, then when I plug in my GPS to my laptop, that I get a weekly GPS Satellite Fix, plus a MapShare update.
I have mine set to accept only "verified" MapShare files.
I update my TomTom on a weekly basis. If you're not doing the same, then you're bound to have old, outdated information, old satellite information, etc.
The electronic equipment is only as savvy as the end user.