As I've reported on my flog -- Food. Drink. Other stuff. -- Disney has done away with prime rib in buffet service restaurants such as Boma. Instead, whole strip loins will be sliced and served.
The executive chef told me it was done for quality purposes: people at buffets want only a sliver, a sample, and prime rib is meant to be cut into bigger slabs. Still, you can't help wondering if there's another reason -- strip loins cost less than prime rib.
Prime rib will still be available at various full-service restaurant throughout the World.