There is roughly 1 million behind according to VG...

Looks like Sega's Masanao Maeda underestimated the power of Sonic and Mario in the same game. Back at TGS last year he claimed that Mario & Sonic At The Olympic Games would sell four million copies, matching the sales of the original Sonic the Hedgehog on the Sega Genesis. Expectation met, and neatly surpassed. In three months the title has sold over five million copies worldwide as gamers flocked to the store in droves to witness what sort of train wreck occurs when you let Sega screw around with both their own characters and Nintendo's, while parents bought up copies because it was the most kid friendly game they could find without Billy Ray Cyrus's daughter on the front cover. Since they mention both in the press release, I am assuming this covers both the DS and Wii versions of the game, but they're equally mediocre so I'll allow it. Congratulations Sega for proving once again that a game can sell based on characters alone.

Mario & Sonic at the Olympic Games™ Hits 5 Million in Global Sales

Founding Fathers of Video Games, SEGA and Nintendo, Find Winning Formula with First-Ever Pairing of Famous Mascots

TOKYO--(BUSINESS WIRE)--SEGA® Corporation today announced that its history-making video game title, Mario & Sonic at the Olympic Games™, has sold five million copies worldwide in just over three months. Developed by SEGA for the Wii™ video game system and the Nintendo DS™ system, with creative input and executive milestone approvals by Nintendo's developers, the title brought together for the first time the two most beloved icons in the entertainment industry. In the spirit of the Olympic Games, the legendary mascots also brought friends from their storied franchises along, including Luigi™, Knuckles™, Yoshi® and Tails™, to compete in a variety of Olympic events.

"With adored icons and fun game play, Mario & Sonic at the Olympic Games has shot to the top of the sales charts and is clearly resonating with the growing audience of casual gamers that want an engaging and accessible gaming experience," said Simon Jeffery, President and COO, SEGA of America.

Published by SEGA across Europe and North America, and by Nintendo in Japan, Mario & Sonic at the Olympic Games made its worldwide debut on November 6, 2007, when the Wii version hit store shelves in the United States. According to the NPD Group, which tracks sales data in the United States, the game was one of the top-ten best-sellers in the United States - across all platforms - in the critical holiday sales month of December.

When Mario & Sonic at the Olympic Games launched in Europe just days later, it was an immediate hit, rising rapidly to the top of sales charts. Mario & Sonic became the best-ever performing Wii game over the seven-day period that ended on December 11, 2007. In January, Mario & Sonic was the best-selling video game in England across all formats.

"The market for entertaining games that everyone can enjoy is growing faster than any other segment in the industry, thanks in part to the explosive popularity of Wii and Nintendo DS," continued Jeffery. "A key element of our growth strategy at SEGA is to develop and publish games that appeal to this expanding market."

Mario & Sonic at the Olympic Games is licensed through a worldwide partnership with International Sports Multimedia (ISM), the exclusive Interactive Entertainment Software licensee of the International Olympic Committee (IOC).