Customers are flocking to stores to buy Wii U consoles that come paired with Mario Kart 8. 82 percent of sales of Wii U consoles last week were systems that included the game according to retail monitor Chart-Track.

In the U.K., sales of Wii U hardware soared 666 percent thanks to Mario Kart.

And in Sony and Nintendo's home country, Japan, Wii U's are outpacing sales of PlayStation 4. Japanese gamers aren't excited with PS4's game offerings like Americans and Canadians are.

In North America, customers are grabbing Sony's PS4 in large numbers and less of the Wii U consoles.

Wii U sales were disappointing from last March to March 2014 and Nintendo hopes that the recent excitement for the new Mario Kart game will continue.

In the fourth quarter for Nintendo which ended March 31 of 2014, Nintendo reported sales of only 310,000 Wii U systems.

Gamers are delighted that their copies of Mario Kart 8 comes with a free game download as well.

And reviews of Mario Kart 8 have been excellent.

"The early response to Mario Kart 8 demonstrates that the best days for Wii U are still ahead," Nintendo of America president and COO Reggie Fils-Aime said in a statement. "This year's E3 is just days away, and it will be all about the future games for Nintendo platforms. This milestone is a great place to start!" 

Still, the Wii U is trailing far behind Sony's Playstation 4 and Microsoft's Xbox One. Expect Nintendo to bring some surprises at the E3 conference.

In other Wii U news. a new Wii U update surfaced Tuesday. This update allows users to see their 10 last played games and apps. It also delivers "a better user experience."

The new update will be automatically applied to the Wii U system as long as the user has their console connected to the Internet.