The Shimano hubs have cones.

A couple of years ago I was having trouble with my stock front wheel (since replaced). I had the wheel trued just before a tour, and ended up breaking 3 spokes in about 800 miles. They were breaking at the threads at the base of the nipples, which is unusual. My theory is : When the shop trued the wheel, the nipples were semi-seized, resulting in the spoke twisting until the threads broke loose during the truing operation. I think this twisting action affected the strength at the weakest point, the threads. I believe that anti-seize compound or spoke-prep would have prevented this problem.