Microsoft this afternoon released new data on Xbox 360 results, saying that cumulative worldwide sales of the video-game console have now reached 28 million units. That's up from roughly 25 million before the holiday shopping season. Based on its estimates, the Redmond company says it expanded its lead over Sony's PlayStation 3 to a margin of 8 million units worldwide.

Nintendo's Wii remains the runaway leader in the market, with more than 45 million units sold, according to this VGChartz.com tracker.

Earlier reports said the higher-priced PlayStation 3 struggled during the holiday season. But the growth seen by Nintendo and the Xbox 360 also seem to confirm the theory that video games, overall, are well-positioned to weather the global economic turmoil.

Microsoft's Aaron Greenberg said 2008 was the biggest year in Xbox history. In addition to growth in console sales, the company says it now has more than 17 million active users of its Xbox Live online gaming service, up from 14 million in October, while consumer spending through the company's Xbox Live Marketplace was up 84 percent year over year.

We'll post numbers from Sony and Nintendo as they're available.

Update: Here's a statement Sony issued this afternoon from Ian Jackson, VP of Sales, Sony Computer Entertainment America:
 
"We've had a solid holiday season and have delivered consistent growth throughout this year. 2008 was a pivotal year for PlayStation with the best software line up in the industry, a dramatic expansion of PlayStation Network including the launches of the video delivery service and the beta of the PlayStation Home, as well as extended hardware offerings with the PSP 3000 and Uncharted 160GB PS3 bundle. Early internal data points to an increase of more than 130 percent of PS3 hardware sales for the holiday season (since Black Friday) and we’re also seeing a growth of nearly 40 percent in total PS3 hardware sales for the calendar year. We remain confident this momentum will continue into the new year.”