The Japanese console maker said Tuesday it reached the milestone 15 months faster than the industry's best-selling console, Sony's PlayStation 2. Nintendo launched the Wii in November 2006, the same time Sony released the PlayStation 3.
Nintendo sold 70.9 million Wiis worldwide as of the end of March, a pace that could lead to the console surpassing the PlayStation 2 in total sales. Sony has sold 140 million PS2s.
A key component to the Wii's success has been its motion-sensing controller, which lets the people control game play by moving a wireless, handheld device. The technology opened up the Wii to the broader market of casual gamers, as opposed to the more hard-core gamers who favored the PS3 and Microsoft's Xbox 360.
While Nintendo has enjoyed the benefits of technological exclusivity with the Wii, that's about to change this year, when Sony and Microsoft plan to announce their own motion-sensing add-on to the PS3 and Xbox 360, respectively.
Microsoft's Kinect, which is scheduled to be released in early November in the United States, is the most innovative of the two devices. The system comprises a camera, audio sensors and motion-sensing technology to track human body motion.
The Wii and upcoming PS3 systems require users to hold a special device. Sony plans to release its PS3 Move add-on in the U.S. in mid-September.
Whether Sony and Microsoft can close the gap in unit sales with the Wii remains to be seen. However, the latest motion-sensing devices are likely to remain the focus of the industry until the console makers ship their next-generation systems, possibly in 2012.
In the meantime, console makers have been driving U.S. sales through price cuts, while the industry as a whole is in a slump. The video-game industry in July saw a 6% decline in sales to $1.1 billion, according to The NPD Group. The drop marked the ninth monthly decline in the last 12 months.