Canon's sophisticated SuperRange Optical Image Stabilizer combined with Intelligent IS helps correct camera shake, so even hand-held video taken at long focal lengths is sharp and steady.
Taking photos and videos in low-light situations has always involved some kind of tradeoff: you can either crank up the ISO and reduce image quality significantly, use something like Sony's NightShot and add that alien green tint to everything, or trust your image stabilizer to go from wacky-blurry to just pretty-blurry.