Across the top we have the function keys which are Expose (F3), Dashboard (F4), F10, F11, F12 are now the volume controls. F1 and F2 are brightness controls (from off to ouch that hurts!) and F5 and F6 are the keyboard glow controls. The other keys are left for the media controls.
The trackpad is a very wide unit and it works extremely well even for those with big hands. The Air fully supports multitouch gestures and although this is a great feature for resizing and rotating images it has yet to gain much 3rd party support. It is cool however to move back and forward pages in a browser with the gestures. The trackpad, all in all is one of the best I have used. The buttons below the trackpad have also been increased in size and should be easier to use for the majority of people.