As Jim C said, motion is more likely going to be noticeable from winds across the ship's beam (sides) than from waves. Most modern ships have large flat sides which is referred to as the sail area. The worst cruise we've been on for ship motion had nothing to do with the water. Seas weren't perfect but they were less than 10 feet. What killed us was the trade winds were running 30 to 40 knots and always coming from the side and there was no way to avoid it given our course. It was the one cruise where I looked forward to the ports.
It is also correct that the Oasis encountered 65 to 70 foot seas on it's transit from the shipyard to Florida. They also had 65 knot winds but were able to sail into them. The waves seriously damaged the forward two rescue vessels but otherwise the crew told me (I was aboard a couple weeks later) it really wasn't that bad of a ride.