Need I say more? Actually, yes. Just wait for the CTS V-Series!
Best Concept Vehicle: Chevrolet Volt Consider the hybrid reinvented. The Volt is technically a "concept car", but the idea is being prepared for production. The vehicle is completely driven by electric motors allowing it to run off virtually any power source. Plug it in (pulling electricity from such sources as wind, coal, hydro-electric, nuclear, geothermal, etc.) to charge and travel 40 miles purely on battery. If you need to go further you can fill up the built in generator with any number of fuels (ethanol, gasoline, biodiseal, and conceivably hydrogen when that day comes) to recharge the battery on the fly, allowing you to travel significantly further and achieve 150 MPG!