Watch Australian motor racing legend, Mark Skaife, and EV Engineering CEO, Ian McCleave, touring the all-electric, battery-switchable Holden Commodore prototype. For more information on the EV Engineering project go to: http://www.evengineering.com.au/
I believe that this is the project I recently read of where Holden did not make this conversion, but an independent team set up a shop down the road from Holden's offices and did the conversion on their own.
Holden is an Australian car company owned by GM - rather, in GM's press releases they talk of Holden as one of the 30 some odd "brands" owned by GM.