Initiates a revolution in gaming, creating a desire to exercise and be active as opposed to vegging in a sofa for hours.
The team that designed Wii Sports was very smart, indeed. By creating a game that gets people off their butts, you create adreneline, build up a sweat, and get your heart pumping - something that's been absent in the past but is fulfilling a growing need in everyone to want to be fit, eliminate stress (good endorphines). Playing other games doesn't do anything except create a sense of depression and frustration (bad endorphines). So you end up with a great sense of accomplishment even if you lose the match in a game of tennis, because you're burning calories and building up your cardio vascular system.
Very smart, Nintendo.