The MacBook Pro resembles the 15-inch PowerBook G4 that it replaces, clad in aluminum and weighing the same 5.6 pounds. It's slightly wider (14.1 inches) and slimer (9.6 inches), but still fits in the padded compartment of a computer bag. (The 12-inch and 17-inch PowerBook G4 models are still available, though Intel-powered models will no doubt replace them later this year.)

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