They are now called Sea Raycers.
Found this online:
"The vessels with the most appeal--the new fleet of Sea Raycers (they replaced the Mouse Boats)--have sporty little engines that reach speeds of 18 mph on Disney's lakes. Rented on a first-come, first-served basis ($21.59 plus tax per half hour), the Sea Raycers carry two passengers. All the marinas offer them to guests for exploring the waters around the Contemporary Resort, Wilderness Lodge, Fort Wilderness, Yacht and Beach Clubs, Caribbean Beach, Port Orleans, and Coronado Springs."