Don't actually do the car velcro mount. There's a reason every car owner's manual says to never do this - if the airbag deploys, the passenger will have the iPad embedded in their skull.
Lots of tourers stick a paper map up there. If it's the 3G iPad following your location with the Little Blue Dot™, you could glance down to see upcoming streets/turns/merges. But yeah, for God's sake don't multitask on a motorcycle.
In matters of real-world safety, hard rules like "never attach it there" are MUCH better heuristics than "don't attach it there in the wrong situation."
don't leave it there if you have a front seat passenger
Even if you try really hard to mount the iPad such that it is precisely centered on the passenger-seat air bag -- which you probably won't do; that's awfully far away from the driver -- how sure are you that an air bag deployment won't launch the thing toward the driver? Or cause a ricochet?
Not all that sure. However I do know that it's pretty low on the list of things that are likely to kill me in the event of a car crash.
If I want to optimize for the minimization of my small yet non-negligible chance of dying in a car crash I'd gain a much larger effect by trading in my current car for a Volvo rather than removing my dash-mounted iPad. I'd get an even better effect by improving my driving habits; not listening to music while driving, never ever exceeding the speed limit and only driving when absolutely necessary.
But sometimes we trade off safety for convenience.
"Professional strength" velcro is some tough stuff. Kept a huge board heavier than an iPad on the wall for two years; when I had to remove the velcro from the wall, it took chunks with it.
It's corny and silly, but as an instructional video, it's excellent. No dialog, no wasted effort, just teaching and demonstration in action. Feels like the first 40 minutes of WALL-E.
