Um, wow. Ol' Steve just hopped off the stage at Macworld, and once again has left us with our mouths open. The MacBook Air ($1,800) is the world’s thinnest laptop. Measuring only 0.16 to 0.76 inches and weighing 3.0 pounds, the MacBook Air sports a 13.3-inch LED-backlit widescreen display, a full-size backlit keyboard, a built-in iSight camera, and an iPhone-like trackpad with multi-touch gesture capability. The MacBook Air has five hours of battery life and comes with a 1.6GHz Intel Core 2 Duo chip (upgradeable to 1.8GHz), 2GB of RAM, an 80GB 1.8-inch hard drive (there's an option to add a 64GB solid-state drive), and Wi-Fi and Bluetooth. Anything missing? Oh yes, the disc drive. Fear not — Apple is selling a matching MacBook Air SuperDrive ($100) or you can just use the new Remote Disk feature to share the optical drive of a nearby computer.