Sales of video games for consoles are expected to have fallen to $365 million in the United States in September from $458 million a year earlier, Wedbush Morgan Securities analyst Michael Pachter forecast in a client note. Pachter said he expects double-digit declines for September and October.

"We expect modest growth in November and dramatic growth in December," with full-year console video game software sales ending 9 percent higher year-on-year, Pachter said. U.S. console video game software sales are up 9 percent through August, he added. September sales figures from market researchers NPD Group are due later this week, Pachter said.

Video game sales have slowed as consumers wait and save for next-generation consoles from Microsoft, Nintendo and market leader Sony. Microsoft's Xbox 360 will be first to hit the market and is slated to arrive on store shelves on November 22.

Pachter forecast a 2 percent rise in September sales at Electronic Arts, the world's biggest video game publisher, and a 4 percent increase at Activision, the industry's No. 2 player.

Sales at Take-Two Interactive Software, which recently pulled and re-released its blockbuster "Grand Theft Auto: San Andreas" title without disabled sexual content that let to a restrictive rating change, is expected to have September sales that were down 24 percent from the year earlier.