OS X Lion Inverted Scrolling Automation Shortcut

This ought to do it:

tell application "System Preferences" to set the current pane to "com.apple.preference.mouse"
tell application "System Events"
    tell process "System Preferences"
        click radio button "Point & Click" of tab group 1 of window "Mouse"
        click the first checkbox
    end tell
end tell

Final Working Solution:

tell application "System Preferences"
    activate
    set current pane to pane "com.apple.preference.trackpad"
end tell

tell application "System Events"
    tell process "System Preferences"
        click radio button "Scroll & Zoom" of tab group 1 of window "Trackpad"
        click checkbox 1 of tab group 1 of window "Trackpad"
    end tell
end tell

tell application "System Preferences"
    quit
end tell