The BlackBerry trackball brings a slight blush to our cheeks — fiddling with a tiny nub just strikes us as a little bit dirty. (Credit: RIM) We hope we'll feel the same frisson of forbidden user-interface-element excitement when we get our fingers on the new "optical trackpad", which is replacing the trackball on the BlackBerry Curve 8520. We haven't tried it yet, but we're told that the trackpad acts like a tiny version of the mouse pad on a laptop — although RIM assures us it's insanely responsive to make up for its small size

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BlackBerry Curve 8520 swaps balls for pads