The video game industry had sluggish sales in May 2011 according to data recently released by the NPD Group. "May 2011 was the lowest month of sales for the industry since October 2006," analyst Anita Frazier wrote, blaming "a light slate of new releases.”

Unsurprisingly, Rockstar's latest, LA Noire, released mid-month, managed to climb to the top of the sales list.

Hardware sales improved, with the PS3, PSP and Xbox 360 all experiencing year-over-year increases. Xbox 360 continues to top the charts, with the platform now commanding 34% of the industry's year-to-date revenue. Combined, the PS3 and Xbox 360 are up 28% for the month, partially offsetting the declining sales of the Wii. Before rushing to the forums to make fun of Nintendo fanboys, Frazier notes that "a year from now the Wii will still enjoy the lead in install base" if the current consoles continue their current pace.

According to Frazier, "sales of the 3DS were light," but next week's release of Ocarina of Time 3D should change that. "We will begin to see a slate of strong content come to market for the 3DS, which should help to significantly boost sales of hardware during the remainder of 2011."

Remember, there's a caveat to remember while looking over the figures provided by NPD. The organization doesn't include digital sales in its monthly report, and the recent Escalation map pack for Call of Duty: Black Ops "undoubtedly ... shifted some dollars that might have been spent on new physical content at retail."

Top 10 US physical retail games - May 1 to May 28, 2011

1. L.A. Noire (360, PS3)

2. Brink (360, PS3, PC)

3. Lego Pirates of the Caribbean: The Video Game (Wii, 360, NDS, PS3, 3DS, PSP, PC)

4. Portal 2 (360, PS3, PC)

5. Mortal Kombat 2011 (PS3, 360)

6. Call of Duty: Black Ops (360, PS3, Wii, NDS, PC)

7. Zumba Fitness: Join the Party (Wii, 360, PS3)

8. NBA 2K11 (360, PS3, Wii, PS2, PSP, PC)

9. Just Dance 2 (Wii)

10. Lego Star Wars III: The Clone Wars (Wii, NDS, 360, PS3, 3DS, PSP, PC)