Most sources I have ever seen (wiki and howstuffworks, to name a few) use "electric motor" vs "gasoline engine" - at least just for the sake of convention.
Anyways, I think its an important issue to bring up because great AC induction motors are what defined the EV-1 and the projects that sprung up in its wake (pun intended).
The Wally Rippel blog on Tesla's site is really great because of how straightforward and honest it is about the pros and cons of each design. One of the key points he makes is how AC induction tends not to lose efficiency at higher power and at higher loads, unlike brushless DC. So in that regard, it'll be great for making a 160hp motor for the Volt. DC motors are more expensive to build cuz of the permanent magnets, but it takes way less engineering to get them to work, so in that regard it makes sense why GM used a brushless DC motor to get the autoshow Volt to move 10 feet onto the stage.