There's a standard the car companies have been working on for charging connectors. This is one step towards widespread adoption, in that if there's a commonly agreed-to plug then that plug could be available "everywhere" and "anybody" with an electric vehicle could pull up to a charging station and use that standardized plug.
In the old days before last time GM killed the electric car there were two plugs being used. One was an inductive paddle used by GM in the EV1 and was in at least another vehicle. The other was the Avcon connector, used by the other EV's from major car companies. They didn't work with each other meaning the companies who installed charging stations had to install both kinds. Further those charging stations were not cheap, those charging stations have a big box with a lot of smarts in the box. For example the box that had the Avcon connector talks to you all through the charging process e.g. telling you how many kilowatt-hours you put into the car. There were a large number of these stations installed throughout California, so I've seen them here and there.
The J1772 is not either of those connectors.. That was just a little divergent detour of my mind.
If this connector truly does become in widespread use then it will be important. Some articles discuss it as being 440 volt and allowing rapid recharge. Rapid recharge will clearly require high voltage. I wonder if this will also support lower voltage and lower recharge rates?
Car Companies Standardize Plug for Electric Vehicles
Plug Standard Needed For Electric Car-Charging Cord Interface: SAE J1772
Automakers and utilities reach agreement on plug-standard
http://engineers.ihs.com/document/abstract/MPPZTAAAAAAAAAAA
Apparently they've been working on this since 1998: http://www.theautochannel.com/news/press/date/19980527/press012917.html
Task force home page: http://www.sae.org/servlets/works/committeeHome.do?comtID=TEVHYB3
Coulomb Technologies is using this connector: http://www.pr-inside.com/coulomb-technologies-to-showcase-the-r945315.htm
The EV Discussion List has some research on the J1772
