At 11:19 AM 8/30/2010, Don Hanson wrote...
>  My carefully recorded tire data shows that a nitrogen-inflated
> tire's pressure increased an average of 4psi less than one filled
> from an air compressor.

Yes, humidity can play a factor. But there's nothing magic about
nitrogen - except that it's the cheapest and most readily available dry
gas. For shop use, adding a dryer to the compressor is cheaper, easier
and less bulky than a N2 tank.

Of course, none of this matters on a Vanagon, where N2 adds no value.