I seriously doubt Harley is going to invest a bunch of money in a new engine design and then go backward by eliminating water cooling. For those who seem to think oil cooling the heads is some magical system that will let them avoid those nasty ugly radiators, think again. A true oil cooling system will need a large radiator, otherwise called an oil cooler, so all you do is swap one ugly heat exchanger for a different ugly heat exchanger, unless they plan to hide it under the seat and duct air to it. Built in heated seat, whether you want it or not. Probably work wonders on the electronics also.
Personally, I still think it's really just an electric motor underneath a plastic mock-up of a traditional looking engine.
Jerry