As promised, Microsoft's top video game title, "Halo 3," on sale for less than a week in September, fueled the company's broader video game business, according to just-released numbers from researcher NPD Group. (Update: Turns out NPD counts September differently than I do. Their September is longer, so the figures in this story actually represent 12 days of sales.)

NPD analyst Anita Frazier called the 3.3 million copies of the game sold in the U.S. last month "phenomenal." That figure was nearly double the total units sold under the next nine best-selling titles in September. (It also includes copies that eager fans pre-ordered online in the months of hype leading up to the game's release.)

"True to its name, the game rubbed off on hardware sales too -- the Xbox 360 realized it's best month ever in unit hardware sales outside last holiday season," Frazier said in a statement. "If ever there was a doubt that great content drives hardware acquisition, this should put that doubt to rest."

For the first time in several months, Microsoft's Xbox 360 outsold the Nintendo Wii, which also had a stellar September.

Here are U.S. console sales for September, from NPD:

Xbox 360, 527,800

Wii, 501,000

PlayStation 3, 119,400

PlayStation 2, 215,000

Next month's report will show whether today's PlayStation 3 price cut by Sony will juice its sales.