The meta/gallerycss-csslist.json file lists the current version of the module.

0.2

Add support for .yui3-menu-heading. This involved adding styles to the .yui3-menu container (namely, width: 100%), and making the .yui3-menu-horizontal ul { display: inline-block; }.
Improve support for IE7, especially display: inline-block hack.
Remove .yui3-menu-light, and .yui3-menu-dark. This was done for k-weight and you can easily achieve this style by styling your own menu.
Remove background gradient on hover, instead replace it with a single color. The gradient was overkill.
Improve the :hover rule for .yui3-menu li a. It was previously using :not and was failing in IE8 and below.
Rename .yui3-menu-active to .yui3-menu-selected to keep in sync with other YUI widgets.

0.1