I haven't had any framerate problems at all. Even when I'm in water, it's still just fine. The only thing I could say, is at the beginning after you press start, there is sort of a pause, and then it picks up. Other than that, nothing has happened.
I'm on a Samsung HDTV that goes up to 1080i, with my 360 running at 720p with the official 360 component cables (dunno if that makes a difference). My TV does have HDMI input, but I don't use it anyways, since my 360 was made before they started adding the HDMI ports in the back.
Don't see why you guys would be having that problem.

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