From the top of the registration page at the website:
Registration Details
Check-In
All attendees, both those who have pre-registered and those registering at the door, need the following to check in:
Photo ID
Parental permission form if under age 18
If you are pre-registered, then you also need:
Your badge/membership card, if you opted to have it mailed
Note that it does not specificy government issued ID for check-in.