North Carolina has white rhinos in a huge multi-species area, and Disney's rhinos (both species) are in terrific exhibits. Brevard looks good, and both Tampa and Audubon have large, grassy areas for whites. Indy and Baltimore aren't bad either
Yes you are right. Whites are not really the problem as they are rather common in zoos but Black Rhinos are shafted often. Pittsburgh comes to mind, as does San Francisco, Cincinnati, Dallas, San Antonio, Busch Gardens (The Black Rhino, not the Whites), and more just to name a few.
Its always nice though to see rhinos in a nice large savanna habitat though as they get shafted in many zoos and that goes for the three types that are common in zoos. All future zoo exhibits are mostly planned for elephants. It would really be shocking to see a zoo go out of the way to feature rhinos in a new, expensive state-of-the-art exhibit. Denver will feature rhinos in Asian Tropics and Columbus will have a new modernized Black Rhino exhibit in the African Savanna. Other than that I can't think of any other planned new rhino habitat.