From way way way back it was slated to be a Minion themed parking garage. Not sure if they can do a Potter-themed parking garage per their contract with WB.
So I would count on "Minion parking" for now. Kevin, Stuart and Bob will mark your position.
Back on the Wizarding World, you won't be entering that land anytime in 2015 unless you're a construction worker, an employee or a high-level VIP. Honestly I wouldn't start Potter Watch until March 1st, although once Grinchmas wraps up you're gonna see an advertising bonanza start up. Expect a grand opening date announced just prior to Super Bowl 50, in which Universal will air a commercial for the land.
Lots of foolish people will start crowding around Potter probably as early as February, as that's when all scaffolding and construction will be non-existent from a guest's POV. It'll be a long winter, that's for sure.