Microsoft on Thursday said sales of the Xbox 360 video-game console have topped 30 million units globally since its release in 2005.

While the milestone is significant as an indication of the Xbox 360's popularity, the number is far behind the Nintendo Wii, which surpassed sales of 50 million units in March. Nintendo launched its console a year after the Xbox 360 made its debut.

However, Xbox 360 sales have surpassed those of Sony's PlayStation 3, but Microsoft's console has been available for a year longer. Since launching the console in November 2006, the same month the Wii debuted, Sony has sold 22.73 million units, as of March 31.

Microsoft and Sony have boosted sales by dropping prices of their respective consoles. Nintendo, however, has maintained the same $250 price on the Wii since its release.

Microsoft also reported that membership in its Xbox Live online gaming service has topped 20 million subscribers. Microsoft launched Xbox Live in November 2002.

Despite the milestones, the video-game industry hasn't been immune from the economic recession. In April, overall sales of games, hardware, software, and accessories fell for the second consecutive month. Along with the dismal economy, the absence of major video-game releases contributed to the decline.

Sales of games fell by 17% to $1.03 billion, hardware 8% to $391.6 million, software 23% to $510.7 million, and accessories 15% to $129.5 million.

The biggest surprise was the 43% drop in Nintendo Wii console sales from March to 340,000 units. The Wii, with its popular motion-sensor control, has regularly sold out at retail stores since its release in late 2006. Nintendo has had to increase production to meet demand. The latest numbers are significant because they're an indication that demand is now being met, according to analysts.

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