The Not Too Distant Future of CSS - The CSS - page 255

img {
/* for Firefox 4 */
-moz-transition: -moz-transform 0.5s ease-out;
/* for Safari and Chrome */
-webkit-transition: -webkit-transform 0.5s ease-out;
/* For Opera */
-o-transition: -o-transform 0.5s ease-out;
/* W3C specification */
transition: transform 0.5s ease-out;

}
img:hover {
/* for Firefox 4 */
-moz-transform: scale(1.5, 1.5);
/* for Safari and Chrome */
-webkit-transform: scale(1.5, 1.5);
/* For Opera */
-o-transform: scale(1.5, 1.5);
/* W3C specification */
transform: scale(1.5, 1.5);

}
[...]
<img src="images/hover_me.png" width="90" height="90"
➥

alt="Hover Me" />

The Mozilla Developer Center has a thorough article on working with
transitions at https://developer.mozilla.org/en/CSS/CSS_transitions .

CSS transitions are supported in Safari 3.2+ Chrome 3+, Opera 10.5+,
Firefox 4+, and Internet Explorer 9+.