I was able to follow-up with Tim Grieg, the Volt's chief interior designer via email to gather some more details.  Thanks Tim.

I asked him three questions:

1. What are the data options the center display will provide?
Too many to list in a single e-mail, but the CENTER display (on top of the Integrated Center Stack) will display audio, climate control, navigation, and the Volt page where the customer can program when to charge the vehicle, for instance. The display in front of the driver will show vehicle speed, total range (electric range and fuel range), total miles driven (total EV only miles and total fuel only miles), a trip odometer (again, with EV trip and fuel trip), and an efficiency meter, which will help customer fine-tune their driving to maximize their range. Other features that show up in the display in front of the driver will include information like tire pressure, etc.

2. Will the car have Internet access?
No Internet access, but I can say that GM will take advantage of what OnStar can do for our customers to expand the "experience."

3. Will leather be an option and what is the other material?
The Volt will have 2 trim levels -- one fabric and one leather.