NPD gave Shacknews the North American software sales numbers for the month of August today, with the top two spots taken by the Xbox 360 version and PlayStation 2 version of EA Tiburon's Madden NFL 08. This reverses previous year trends, as the PlayStation 2 version of Madden NFL 07 outsold the Xbox 360 version by about 1 million units in 2006.

The 360 Madden stiff-armed its way to 896,600 homes during the game's first month at retail, a considerably higher amount than the 643,600 PS2 versions sold. Using Madden sales as a relative measure of console popularity, it would seem the mainstream move to current-gen consoles has arrived. This shift is seen further by the Xbox 360's 276,000 units shipped during August, beating out the last-gen PS2's 202,000.

Taking third place in software sales was the Xbox 360 version of 2K Boston/2K Australia's underwater shooter BioShock, selling 490,900 units during the month. Nintendo-published Wii titles like Retro Studios' Metroid Prime 3: Corruption took four of the top ten spots in August.

Overall, year-to-date software sales are up 22.0% to $3.8 billion compared to 2006, with August having a 22.5% year-over-year increase in sales to $488 million. Check out the complete list of the month's top-10 best-selling software below

1. Madden NFL 08 (X360; EA Tiburon, EA Sports) 896,600 units
2. Madden NFL 08 (PS2; EA Tiburon, EA Sports) 643,600 units
3. BioShock (X360; 2K Boston/2K Australia, 2K Games) 490,900 units
4. Madden NFL 08 (PS3; EA Tiburon, EA Sports) 336,200 units
5. Wii Play (Wii; Nintendo) 256,800 units
6. Metroid Prime 3: Corruption (Wii; Retro Studios, Nintendo) 218,100 units
7. Mario Strikers: Charged (Wii; Next Level Games, Nintendo) 147,400 units
8. Guitar Hero 2 (PS2; Harmonix, RedOctane/Activision) 145,400 units
9. Mario Party 8 (Wii; Hudson Soft, Nintendo) 138,300 units
10. Guitar Hero Encore: Rocks the 80s (PS2; Harmonix, RedOctane/Activision) 127,100 units