DigitalCameraInfo has published an article that compares the optical image stabilization systems of five point and shoot digital cameras. They compare the Nikon Coolpix P3, Panasonic Lumix DMC-FX50, Pentax Optio A10, Sony Cyber-shot DSC-T30, and Canon Powershot SD700 IS.
Many digital cameras currently on the market have mechanims for image stabilization/anti-shake/shake reduction and so on. However, the DCI article concentrates on "optical image stabilization" which, by their definition, means that the camera moves a component of the optical system to compensate for movement. On most digital cameras, a lens element is moved to compensate for hand shake and on others, the imaging sensor is shifted to provide the stabilization. In their comparison, the only camera that used the sensor-shift method was the Pentax Optio A10. With optical image stabilization, you can take blur-free images at much slower shutter speeds than you could without stabilization. For example, if you want to take a shot with a shutter speed of 1/20 of a second and hold the camera in your hands, it's very difficult without stabilization to make a blur-free image. With image stabilization, that shutter speed stays the same, but the optics correct for your hand movement.
Another way that digital camera makers reduce blur is to use electronic methods. They reduce blur by either increasing the sensitivity (ISO) or using an image processing algorithm that analyzes, then corrects, blurry details. However, these electronic methods usually cause a decrease in image quality. For example, if you put a camera in high sensitivity mode, the ISO is increased to make the shutter speed faster to eliminate blur. However, on most compact point and shoot digital cameras, the increase in ISO creates noise, often noticeable as graininess, in your images. That said, the electronic methods of reducing blur are helpful when you have a moving subject. As I mentioned in the previous paragraph, optical image stabilization lets you keep the shutter speed slow without blur. This doesn't help when you're trying to capture someone running - you absolutely have to have a fast shutter speed. If you don't have enough light for a fast shutter speed, you need to increase the sensitivity of the sensor.
In their comparison, DigitalCameraInfo shows some nice "with" and "without" stabilization shots for each camera in their test. They also test the long exposure results and effects of stabilization in the movie-taking abilities of the five cameras. While all cameras were effective in reducing blur in the shots, the Sony Cyber-shot DSC-T30 and Pentax Optio A10 stood out from the pack with the sharpest shots.
To read on and see their sample photos, see the DigitalCameraInfo article here: http://www.digitalcamerainfo.com/content/Point-and-Shoot-Image-Stabilization-Tested-.htm