Take this with a grain of salt but reports are emerging that Microsoft could be relaxing its stance on online content for the Xbox 360 by supporting Valve's Steamworks API on the console. Speculation started a few hours ago after Steam users discovered an 'Xbox support' option buried inside the platform's online support forums. However, so far it remains unclear if this is a hint of things to come or a simple goof from someone maintaining the support page.
Steamworks is currently available only on the PlayStation 3, but Valve has made no secret of their desire to have the service available on the Xbox 360 as well. That said, the company has also made it clear that the decision is not up to them, pointing to Microsoft's reluctance to open up the Xbox Live infrastructure.
A buried menu option is far from conclusive evidence, and as of this writing neither company has come out to confirm or deny any sort of deal allowing Valve's third party content on Microsoft's Xbox 360 platform. Obviously, Steam does not sell or deal with Xbox games so the mention in its support forums is certainly curious.
We'll keep an eye open for any possible announcements at the Tokyo Game Show kicking off on September 15.