If you're a seasoned Mac user, you'll immediately notice that navigation is different in Lion. There's an entirely new set of gestures, some of which are used for two new features: Mission Control and Launchpad.
Mission Control is Spaces' successor and allows you to navigate multiple desktops, full-screen apps, the Dashboard, and all your running applications. Think of it as a bird's-eye view of your desktop, allowing you to quickly access the apps you need.
Launching applications changed, too. Pinch with your thumb and three fingers, and you'll get a tiled view of all your apps, which can be organized into folders and pages--it's called Launchpad. Sound familiar? Apple clearly drew inspiration from its iOS platform.
There's a lot more pinching, pulling, and swiping on the trackpad in Lion, too. So get your fingers warmed up, your Mac out in front of you, and learn to navigate Lion with this How To: