I love the car for its great looks and full size features, yet it's still nimble handling and decent power. Also, despite its size, I average almost 25 mpg, and I'm not a light pedal pusher either. However, I have had similar issues as other owners. The steering shaft, brake rotors, power windows and flickering lights. I too bought an extended warranty and this helped. However, now that it's out of warranty things could get expensive. The steering and brake rotors are my biggest complaint. However, it is a great looking car, definitely fun to drive for a full size vehicle and thus far, reliability really hasn't been an issue, mostly a few modest annoyances.
Styling, interior display and lighting, comfort and good handling and good mpg. It also has a nice exhaust sound.
For GM - if you know you have a problem, don't just fix it under warranty -- admit there is a problem and fix it so the customers don't have to pay for it again when the vehicle goes out of warranty.