My point was that you're not given a choice between OS X and XMB... They do entirely different things.
If you want to compare multimedia interfaces, you'll want to use Front Row for a bit and then compare that to the XMB. OS X is not a multimedia interface. It's an operating system made to be used in full-scale computing. It's not as if you can design a website, encode video, organize a spreadsheet, or use Photoshop from the XMB.
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