Rockstar Games' LA Noire was the runaway winner in the May 2011 US video game chart, according to data supplied by the NPD Group.

The crime caper notched up sales totalling 899,000 copies on Xbox 360 and PS3 combined, although the split across the two platforms isn't known.

According to a regular NPD poster on NeoGAF, Brink managed 401,000 copies, enough to secure second place, while LEGO Pirates is at No.3, followed by Portal 2 at No.4 and Mortal Kombat at No.5 - the brutal brawler managed a further 292,000 copies.

Call of Duty: Black Ops is at No.6, Zumba Fitness takes seventh place, NBA 2K11 is at No.8, Just Dance 2 at No.9 and LEGO Star Wars III rounds off the Top 10.

"This month's story really is about a light new release schedule as compared to last year," commented NPD Group's Anita Frazier. "There were 42 new SKU's introduced in May as compared to 58 last May, and 72 in 2009.

Frazier added: "As a result of a lighter release slate, promotional activity at retail and in circulars was reduced as well, which undoubtedly affected not only planned but impulse purchases."

She continued: "For the month, unit sales were down across all platforms except for Xbox 360, which was essentially flat to last year (+1%)."

Some of this decline can be attributed to the grown of the digital market, says Frazier.

"Keep in mind that purchases of content are increasingly occurring in digital format, and May saw a notable digital release in the second map pack for Call of Duty: Black Ops which was titled Escalation. Undoubtedly, this shifted some dollars that might have been spent on new physical content at retail," she explained.

LA Noire and Brink stole the show in May 2011, but each game achieved lower sales than the top two titles in May 2010. It was Rockstar Games' Red Dead Redemption which came out the victor with a combined 1.5 million copies sold, while Super Mario Galaxy 2 came in at No.2 with 563,900 copies.