I think rural areas have been more peaceful -- but it depends on who is moving into them and from where. Many of the farmworkers are coming from the slums of Mexico City or Juarez -- they never did farm work before in their lives and many see drugs and crime as a better way of getting money than hard work. The hard working farm workers tend to come from the more rural regions of Mexico where they've always worked hard and don't mind physical hard work --- but that's not all of them.
Thats what I have been hearing from a friend in Arizona.