The video game industry took a nasty dip in the month of May.

According to industry tracker NPD Group, the video game industry fell 23 percent to $863.3 million, compared with $1.12 billion last May.

Portable hardware was the only category that did not decline from the previous May, due in large part to the DS Lite and DSi systems, which sold 633,500 units in May – more than the PSP, Xbox 360, PS3, and PS2 combined.  

“This is the first month that industry sales have dipped below $1 billion since August 2007,”  NPD analyst Anita Frazier said in an email.

However, it’s somewhat expected.

“May is typically one of the lowest revenue-generating months in any given year for the industry in general,” she added.  

Nevertheless, the impending release of Wii MotionPlus, along with strong software lineups including The Sims 3 (already a big seller), Ghostbusters, Tiger Woods PGA Tour 10, and Virtua Tennis 2009 will likely help the industry.