I think to establish a correlationship you would need to compare only Christian countries, as non Christian countries always tended to have low growth anyway, and Isamic countries have censured internet.
A good comparison would be the growth rate in Christian countries in 1990 (pre internet) with the growth rate of those same countries in 2006. The countries with the highest internet connectivity would mostly be the same countries with the highest fall in publisher growth rates.
Just a casual glance at the statistics indicates that any country with over 200 computers per 1000 people now has 2% or less growth. (one thing to be aware of is this graph shows computers not internet connections, but they likely coincide).