Olympus' five-axis image stabilisation is some of the best out there. The system allows you to usable shoot images in conditions where the results would horribly shaky. This video captures a view of what the shake-free guts look like under the hood. It's hypnotising.
The stabilisation found in cameras like the Olympus OM-D E-M5 II is a sensor-shift system, meaning that it works by adjusting the position of the image sensor in relation to the movement of the camera. It's in the camera, as opposed to in the lens.