GM has spent so much money developing the Volt, and reportedly makes little or nothing at the current price, that I would expect their near-term efforts to be directed towards reducing their manufacturing costs. That may mean few changes in the basic Volt engine or power train, unless they come up with cheaper options.

Minor tweaks that make the car more desirable and help it sell better might be seen, but I would be surprised at any major changes for at least a couple more years.