Another month passed by in the gaming world and Nintendo Wii seems to be untouchable. According to the information released by the research company NPD Group during May Nintendo Wii sold 338,000 units, which means it’s the best selling next-gen gaming console for the fifth month in a row.

In April, Nintendo Wii sold 360.000 units, despite its limited supplies. The Wii was surpassed only by its relative, Nintendo DS which sold 471.000 units.

Despite the launch of Xbox 360 Black, Microsoft saw its Xbox 360 sales going down at around 155,000 units and Sony has another disastrous month with only 82,000 units sold, the same amount as in April.

Luckily for Sony, its PlayStation 2 sold 188.000 units during May and the company’s PSP is still a hit with 221,000 units, but far behind Nintendo DS which sold an impressive 423,000 units for the month.

NPD Group also revealed that overall industry sales were up 49 percent to $815 million for the month, with hardware sales up 79 percent to $221 million.

Nintendo rules also the Top 10 Software with four games in first five:

1. Pokemon Diamond - DS (Nintendo) - 331,000 units
2. Mario Party 8 - Wii (Nintendo) - 314,000 units
3. Spider-Man 3 - PS2 (Activision) - 249,000 units
4. Pokemon Pearl - DS (Nintendo) - 238,000 units
5. Wii Play - Wii (Nintendo) - 227,000 units
6. Forza Motorsport 2 - Xbox 360 (Microsoft) - 217,000 units
7. Guitar Hero II - Xbox 360 (Activision) - 184,000 units
8. Spider-Man 3 - Xbox 360 (Activision) - 140,000 units
9. Command & Conquer 3: Tiberium Wars - Xbox 360 (Electronic Arts) - 138,000 units
10. Guitar Hero II - PS2 (Activision) - 131,000 units