This is a long way off but a new study has been ordered to research the feasibility and need for a passenger rail line running along Grand Avenue from the soon to be completed light rail system to Wickenberg.
The study will take about a year and should answer such questions as costs, infrastructure options, projected passenger traffic etc.
http://www.azcentral.com/community/glendale/articles/2008/07/24/20080724gl-peorail0724-ON.html
