GREATAMERICAparks.com

I have heard some people call it "Bally's Great America," even though I can't find any evidence that it was ever called that. I have, however, seen Six Flags Great America, a Bally company.

Personally I call it Great America, or sometimes just G.A. for short.

I believe that this has always been the policy at SFGAm, but they have just started enforcing it this year.