^-- Are you using Firefox? If you're using IE8 or lower, it won't support it, and currently IE9+ doesn't either, though I'm sure they'll hop on board sometime.
He also didn't include for Chrome/Safar or Opera, or initial values for the transition.
a:link{
text-decoration: none;
color: pink;
font-size: 9px;
padding: 0;
}
a:hover{
-moz-transition: padding1s;
-o-transition: padding 1s;
-webkit-transition: padding 1s;
padding: 0 0 0 15px;
text-decoration: underline;
color: skyblue;
font: bold 12px verdana;
}
^-- Learn that not everyone uses firefox, "-moz-"
You shouldn't just set things for a single browser, because then not everyone gets the same affect.
As well, learn to collapse multiple properties of the same type into a single property, e.g. margin, and font.
Also you set a transition for margin(s), but neither margin has an initial value. You shouldn't use margin to move it though, because then the whole link physically moves, which means the mouse will move off of it, and so the user will have to try and follow the link. Use padding so that the user doesn't have to try and follow a moving link, the link will still readjust, but the user won't have to follow it.
Both of you
See my thread for more CSS properties via the image link in my signature