Nintendo's latest game wants you off the couch

Instead of going after core-gamers -the "Grand Theft Auto" audience of boys and young men -Nintendo has been roping in the whole family, including moms and grandmothers, and getting them playing (and buying) the Wii.

Wii Fit seems to be expanding the Wii's audience even more. In Japan, between 30 percent and 40 percent of people who bought Wii Fit also bought a video game system for the first time, according to Miyamoto.

Mike Hickey, an analyst with Janco Partners, said Wii Fit exemplifies how the appeal of video gaming has expanded.

"It's becoming less threatening, easier to digest," Hickey said.

The game's launch outside the holiday season may also show the industry is maturing into a form of mainstream entertainment. While game companies still make most of their money around the holidays, Hickey and other analysts expects this to change.

"There is no reason you have to be tied to the holiday months any more," he said. "Like the movie business (games are) a legitimate form of entertainment in the non-Christmas tree months."

While some in the industry have questioned how long Nintendo can keep its momentum -after all, more causal gamers may not want to spend every spare dollar on a new video game -analysts are upbeat.

"I don't think we even had the imagination a year ago that Wii Fit could be compared to 'Grand Theft Auto," Hickey said, referring to the popular crime game franchise, whose latest installment shattered sales records when it hit store shelves last month.

If U.S. sales compare to Japan's, Hickey said Wii Fit will likely sell about 3 million copies in its first couple of months, depending on supply constraints.

Cammie Dunaway, executive vice president of sales and marketing at Nintendo of America, said people have responded in "unprecedented numbers to retailers' pre-sales." While the game sold out online, Dunaway said Nintendo wants to ensure there is a "healthy balance" between brick and mortar stores and online pre-orders.