According to a market research company, The NPD Group, U.S. retail sales of video games, which includes portable and console hardware, software and accessories, generated revenues of close to $19.66 billion, an 8 percent decline over the $21.4 billion generated in 2008.

Nintendo's Wii game console sold 3.8 million units in December and set a record for monthly game system sales in the U.S.

Sales of Sony's PlayStation 3 jumped nearly 90 percent to 1.36 million units, followed closely by Microsoft's Xbox 360 at 1.31 million.

Nintendo's "New Super Mario Bros" was the top-selling console and portable game of the month, and finished at No. 3 for the year. Activision Blizzard Inc's blockbuster "Call of Duty: Modern Warfare 2" was the 2009's best-selling game.

Retail sales in the PC game software industry experienced declines, with revenues down 23 percent, generating $538 million in 2009. The total console, portable and PC game software industry generated $10.5 billion, an 11 percent decline vs. the $11.7 billion generated in 2008.

"December sales broke all industry records and underscores the incredible value consumers find in computer and video games even in a down economy," said Michael D. Gallagher, president and CEO of the Entertainment Software Association, the trade group which represents U.S. computer and video game publishers. "This is a very strong way to transition into 2010. I anticipate these solid sales numbers to continue upward through 2010 with a pipeline full of highly-anticipated titles."

Aside from portable hardware which experienced a 6 percent increase in revenue in 2009, all video game categories experienced declines, with the largest decline coming from console hardware (-13 percent). Console software and portable software both experienced declines of 10 percent, while video game accessories experienced a 1 percent decline.

"When we started the last decade, video game industry sales, including PC games, totaled $7.98B in 2000," said Anita Frazier, industry analyst, The NPD Group. "In ten years, the industry has changed dramatically in many ways, but most importantly it was grown over those years by more than 250 percent at retail alone. Considering there are many new sources of revenue including subscriptions and digital distribution, industry growth is even more impressive."