When I did a quick read of the article, one point seemed to stand out -- longer terms of imprisonment correlated with lower crime rates. The article also pointed out some socio-economic factors that correlated with lower crime rates. The point is that there are a multitude of factors that can effect crime rate and I think the best we can confidently say is that there is no evidence to suggest higher gun ownership rates increase violent crime.
Jim's Rules of Carry: 1. Any gun is better than no gun. 2. A gun that is reliable is better than a gun that is not. 3. A hole in the right place is better than a hole in the wrong place. 4. A bigger hole is a better hole.