The Japanese company announced today that based on its internal sales figures Super Mario Galaxy had the strongest one-week debut of any Wii game to date and has also become the best-selling Mario title ever in its first week, with U.S. sales of more than 500,000.

Yes it’s not Halo 3 with million of units sold after the launch, but GameRankings.com lists Super Mario Galaxy for Nintendo's Wii system as the best-reviewed game of all time and Metacritic.com lists Super Mario Galaxy as having "Universal Acclaim," with a score of 98 out of 100.

Super Mario Galaxy represents the first 3D platform in the action series after Super Mario 64 and Super Mario Sunshine. What’s also new with Super Mario Galaxy is that it now features a co-star mode, which allows a second player to collect startbits for shooting at enemies.

The game’s hero, Mario, is followed on his quest through the Universe to save Princess Peach from his nemesis, Bowser. The deeper you go in the game, the more galaxies you have the opportunity to visit.

Since he’s in space, Mario can perform mind-bending jumps unlike anything he’s done before. He’ll also have a wealth of new moves that are all based around tilting, pointing and shaking the Wii Remote.

The gamers will also experience a wide range of interesting effects in the new Mario game, which was first shown at the E3 summit from 2006.

Super Mario Galaxy has enjoyed so much pre-release popularity that the United States’ GameStop stores were hit by no less than 400,000 pre-orders even before November 2007.