To get the most out of your Lion upgrade, make sure to use a Magic Trackpad.
If you are ordering a brand new iMac or Mac Pro with Lion already installed, make sure to order a Magic Trackpad.
In the same way that an iPhone or iPad uses touch gestures to control the device, it is now possible to control your Mac using a number of intuitive gestures on Apple's Magic Trackpad. To scroll, for example, brush two fingers along the Multi-Touch surface to scroll in any direction — vertically, horizontally, or diagonally. To move between pages in Safari, brush left and right along the Multi-Touch surface with three fingers to page forward and back.
Now that I using Lion, I am quickly coming to enjoy using the Trackpad on my MacBook Air to control my computer. The gestures seem natural to me, and easy to learn as well!