Well, in one word...money. This really is a challenge when our economy is floundering. As Americans, I am optimistic that we come up with many solutions. It may need to convince leaders in local governments and corperations to invest in this change. I am not sure now that mandating this is a correct way to go. I think it really is about syntax. I would call it just planing to convert fleets to CNG. Of course, some vehicles would still be gasoline burning and others propane. Local politics is sometimes weird. The main focus here is to make sure the conversion is not made and instead some political project is done.