Shawn is right. You might get some benefits from the nitrogen being dry versus compressed air coming from an air compressor with no dryer (as most of us don't use a dryer on CA). Otherwise the rest is a myth, and the writeup doesn't even have good science to back it up.
Below is an email from a fellow Mogger on the topic:
"The difference between expansion coefficient for dry air (0.003744 cm
Hg/deg C) and that for dry nitrogen (0.003720 cm Hg/deg C) is way less
than 1% - looked it up in the Handbook of Chemistry a few months ago.
If there's water vapor (like 100% humidity at 37 deg C, temp of human
body) in the compressed air, then the expansion coefficient is somewhat
larger, but still small. If there is liquid water droplets in the air,
then the difference can get really big, if the temperature change range
crosses the boiling point of water at the pressure in the tire.
Three other, perhaps more important, considerations:
(1) There is a bit of Argon in Air (0.93%). Being an inert,
mono-atomic molecule, it finds it way right trough rubber tubes/ tires,
given enough time. Loose it all from a tire with 100 psi of air in it
initially, and the pressure drops by about 1 psi.
(2) The oxygen in air is, surprise!, an oxidizer. Oxidizers support
combustion - fast (fire or explosion), or slow (rusting, corrosion,
degradation of rubber). How well oxygen supports combustion is a
strong function of how much of it there is about, i.e. the partial
pressure of oxygen. For dry air at sea level, one Bar, that's about
20% of a Bar = 0.2 Bar, since air has about 21% oxygen (call it 20% to
keep it easy). If you put 30 psi = 2 Bar in your tires, at sea level,
then the absolute partial pressure of O2 in the tires is 20% of 3 Bar =
0.6 Bar. Not so bad. But, put 300 psi = 20 Bar in your tires and you
have over 6 Bar of O2 partial pressure. That's high enough to make
steel rust and rubber degrade pretty fast!
(3) Use an oil lubricated compressor to pump up your 300-400 psi tires
and you now have both a finely atomized fuel (the oil vapor, or maybe
even just a bit of rubber dust) and a LOT of oxidizer (6+ Bar of O2) in
your tires. It's a Bomb! Add a bit of heat - land your plane on the
carrier deck - and it goes off! BOOM!
If I put over 100 psi in my new Mog tires, I might consider using dry
N2. Otherwise, forget it. It's really not an issue when you are
munching along at less than 20 mph in the Altar Dunes with 10 psi in
the tires, or even cruising down the freeway at < 65 mph with 30 psi in
'em."
