Usability of sliding panels
your tab label seems to exist within the content which it is tabbing .. kinda bad, don't you think.
there is no point in using $(document).ready(), just put your script file right before &lt;/body&gt; , and it will already be executing, when the DOM is done.
instead of adding function for each .tab tag's onclick separately, you should read about event delegation and use that
use closures for storing the active tab, instead of DOM. DOM manipulations are slow
setting top and bottom values in CSS fails to do what you want on IE7
animation quality on IE9 is horrid