I actually just read the fine print on Canon's website. Directly under the bottom of the camera is an * detailing what the 64GB card won't do. Looking on the B&H site though, I find it odd that a different size in the same line can have such a huge disparity in write speeds, i.e. just look at the Sandisk ones on there. Not sure if its typo or what but it really makes no sense to me. I've been waiting for the Delkin 256's to actually get released.
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