It won't be at Wolf Point or General Growth. To get the type of tax revenue that everybody keeps talking about, any casino operator is going to demand a huge site with a single enormous gaming floor and ample parking. A — boat would not be big enough, and even if it was, it would raise a fight over the lakefront that makes the Lucas Museum fight look like a polite ladies' luncheon.
If the casino is downtown, it would have to be at the Post Office, CMK/River City riverfront parcels, or the Rezko/Riverside Park property. At a higher cost, you could build it over the Kennedy, Ogilvie trainshed, or Union Station yards, or possibly do some kind of large-scale clearance in the area between the Eisenhower and Roosevelt. There are other large sites out in the neighborhoods (Finkl, IMD, Michael Reese, US Cell parking lots).
Crown Casino in Melbourne: