Sadly the new owner had to sign an agreement which states they can't drive the Batmobile in public:
The Batmobile from "Batman Forever" sells for $297,000
"The Batmobile, which was featured in the 1995 “Batman Forever” movie, starring Val Kilmer, Tommy Lee Jones, Jim Carrey and Nicole Kidman, was recently sold by Warner Bros at RM Auctions. Though estimated at around $800,000, the buyer paid “only” $297,000. And if you think that’s much, you should know that the car cost around $2,800,000 to make ($2.5 mil for the mold, plus extra $300,000 for completion)."