Microsoft is making a profit off of serious 360 gamers by making them pay for extra content for games. Though the move may help Microsoft make some extra money, it also is excluding other gamers who feel that Microsoft may be cheating them out of their money.

LOS ANGELES, California (Reuters) -- New charges for online extras are sharply raising the price serious video gamers pay for Xbox 360 games, a profitable move by Microsoft Corp. , but one that could alienate some fans.

With more than 6 million users, Microsoft's Xbox Live online network has become the key feature distinguishing the Xbox 360 from rival Sony Corp.'s PlayStation 3 and Nintendo Co. Ltd.'s Wii.

More than 3 million Xbox Live subscribers pay a $50 annual fee that allows them to play games online against one another. About 3 million more use the service without an annual subscription, taking the total to more than half Xbox users.

Through Xbox Live, players can buy maps for fighting terrains and other add-ons that are indispensable to serious gamers, usually at a cost of $10 each. Such add-ons used to be free most of the time and the additions can raise a game's cost to $80 or even $100 over its life span .

"The (downloadable maps) are very profitable for us," said Tony Key, vice president of marketing for UbiSoft Entertainment SA, whose Tom Clancy-themed shooters such as "Rainbow Six" and "GRAW 2" are among the most popular games on Xbox Live.

"If you're a 'Rainbow' guy and you don't have the maps, then you can't play a match," said Key, referring to online competitions. "I doubt there will ever be a Clancy game without the Xbox Live component any more. It's now a key part of the game's DNA."

Games such as UbiSoft's "Rainbow Six Vegas" and Activision Inc.'s "Call of Duty 3" can cost as much as $25 million to make, but extra game levels and maps are extremely cheap to produce, by comparison. Key said they required only about 10 percent of a game's development staff.

Maps and other content are also profitable for Microsoft.

Wedbush Morgan analyst Michael Pachter estimates Microsoft charges a royalty rate of 30 percent for most downloads. That means that, for a $10 download, Microsoft gets $3, while the publisher pockets $7.

Pachter estimates the entire downloadable game content market is currently valued at $200 million, compared with $19 billion for overall game software sales last year, but he points out the additional sales have much higher profit margins.

"It's like building an extra room in a house," Pachter said. "It's nowhere near the cost of building the house."

But pricing the downloads is a tricky science that many game publishers, including Microsoft, are still figuring out as they try to balance profit with the risk of alienating gamers who might feel they are being taken advantage of.

Supernouva via edition.cnn.com »