Just as a note on what my traces are and why I do it: TomTom records data about how fast people drive on certain roads at certain times of the day. Also records things like the average wait time at a red light, typical traffic conditions, etc.
I offer to OpenStreetMap the same data; I know we don't really do anything with that quite yet, but my traces are out there so that when someone decides to take trace data and automatically average the speeds across all public recorded traces, you'll have my data. All of my traces are drivable roads -- my rechargable battery used to last me hours, now it doesn't even last 5 minutes; so I *can't* take it on trails; wouldn't get far before I ran out of juice.
I do sometimes edit maps, but it's rare. I don't take traces so that I can edit the public map, I take them so that somebody else can verify their traces or extrapolate useful data from them.
Just so no one gets any ideas, my TomTom GO 920 is always locked up somewhere; even if you find my vehicle the TomTom is with me or in a locked compartment. It's also password-protected so even if you got a hold of it, it wouldn't be much use. You can steal someone else's GPS much easier than you would be able to steal mine. Already had my GPS stolen once; I'm smarter about protecting it now, even with its unusable battery and broken reset button, I still take measures to protect it.