Xbox chief operating officer Dennis Durkin has revealed that more than half of Xbox Live's revenue comes from downloadable content, GamesIndustry.biz reports.
Microsoft has previously said that around half the 25 million people on Xbox Live are Gold subscribers, which amounts to around $600m in fees a year.
Therefore, if downloadable content - avatar clothing, game content, films, Live Arcade games, etc. - exceeds that figure then total revenue for Xbox Live must be $1.2bn or higher.
Given that, it's no wonder Sony's now offering a premium subscription service on PlayStation Network.
Microsoft reports its 2010 fiscal results later this month.