I suppose there's always a chance, but it wouldn't be for a couple of years yet if it happened at all. Not when they can charge $100 for the wireless adapter as an accessory and people will buy it.
What you might see are some new bundles that include the wireless adapter, but I don't think you'll ever see a 360 with wireless built in. At least not until they get the current heat problems under control.
Is there any chance they'll release a 360 with Wi-Fi? I don't want to drop an extra 100 on a wireless router after buying the console.

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