A radio show (certainly not the best source of information) did a test of footballs inflated 2 psi lower than the rec. They said it was easy to detect and easier to squeeze the ball. This make sense to me without doing an experiment on my own.

Advanced NFL Stats has numbers on the incredible non-fumbling of the Patriots on their home turf (not sure how this jives with each team preparing the the footballs for the offense unless the ball deflation operation is conducted in the bowels of the home stadium and not on the sideline).

http://www.sharpfootballanalysis.com/blog/?p=2932