C. Sorrel, "Photoshop CS4 Exploits Mac Hardware Features," Wired.com, Sept. 24, 2008.
The big Mac-specific feature is support for the multi touch pads found on the MacBooks Air and Pro. You can pinch to zoom in and out, twist the image and also "throw" the picture across the screen: if you hold the space bar down, click and drag the image when it is zoomed in and then let go, the picture will continue to move before slowing and coming to rest. It's very similar to the scrolling on the iPhone.
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