The Wii controllers were ooo’ed and ahh’ed over when they first surfaced because the are very obviously different in look, feel, and design from standard controllers for console gaming.
A unique selling feature of the Wiimote are the motions sensors built into the controller. This allowed the gamer to control items on the screen through pointing and movement.
The design process consisted of sketches, models and even asking hardcore gamers what would appeal to them.
Safety: The strap was added to the bottom of the controller along with a warning in every Wii game to use the strap so that the Wiimote doesn’t slip out of the gamer’s grip during movement.
Learnability: The developers were required to roughly maintain the button layout of the Game Cube controllers. Keeping this same layout and general buttons with related uses would allow the gamers to learn how to use the Wiimotes more easily.
Memorability: During development for the Wiimote things like cell phones were brought in for inspiration, the prototype being a controller with the familiar look and feel of a mobile phone. This familiarity with the controller perhaps lent to its memorability with the users.
These controllers introduced a new level of interactivity to the gaming community. It’s success with gamers has spawned even more controllers and even games centered around high levels of interactivity from the users (ex. Wiifit and pad). This can lead to “an intense emotional involvement that comes from being completely involved in an activity”. The book refers to this as flow.
Wikipedia Used as information Source