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During E3, Immersion, the company that holds the patent for rumble technology, issued a press release that stated they had started licensing the rumble to third party peripheral makers. One of the third party companies referenced, Katana, is supposed to begin releasing rumble controllers this September for the “PlayStation”.
Although the press release mentions the “PlayStation”, it’s a pretty safe bet that it’s the PlayStation 3 they’re talking about. This also makes the licensing for a first-party rumble controller look likely as well.
We’ll keep you posted with the latest E3 news as it happens.