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Good news for Microsoft, bad news for the rest of us.
Microsoft has mentioned a new security feature in the Xbox 360 that would allow the machine to accept or reject devices connected to the machine. This means that if any third-party wants to create peripherals for the console, they may have to set up a contract with Microsoft and subsequently pay them royalties on the products sold in order to have their products usable on the console. This could deter many small companies from attempting accessories for the system.