Nintendo has been topping the charts in Japan for months now.  The numbers are in for March and it spells more Nintendo domination:

• 504,000 DS Lite units sold in March
• DS has been selling over 500,000 units each month for the past 12 months
• 263,000 Wii units sold in March
• Nintendo held 19 of the top 50 software spots with over 1.4 million units sold
• Yoshi’s Island was the top seller with 455,000 units moved
• DS software (first and third) sold 2.2 million units

Source: GameDaily