There seems to be some reluctance on the part of the automakers to push plug-in hybrids. There has been some research out there showing that by using plug-ins there really isn’t a energy benefit. All that you are doing is shifting the source of the energy from one place to another. While this may not seem to be a huge benefit, in actuality it really is.
With an oil based economy there are a few sources of oil and very defined paths for how energy gets from these places to the consumer. However, by using the electric grid it very much becomes a free for all. The grid acts as an open market / network allowing energy to come from many different sources. This allows for innovation in energy technology to be plugged into the grid as it becomes viable. Also different techniques can be used in different areas. There is no longer a need to come up with a solution for everyone.
Local generation of electricity will take off in the near future. 50% of energy is lost in transmission, so by generating it locally already there is a huge savings. As micro-turbines and solar begin to reach similar prices to coal and natural gas you will see communities begin to install these.
By allowing vehicles to take advantage of the incremental upgrades in energy technology you are creating a more flexible vehicle and economy. There is no longer a need for major infrastructure changes. That same money can be used for infrastructure enhancements that have wider unforeseeable benefits.