I experienced the same bug as Tim.

The following mess occurred in the CSS after activating Minit.

#wpadminbar .menupop .menupop > .ab-item {
	display: block;
	background-image: url('http://localhost/wordpress/wp-includes/css/../images/admin-bar-sprite.png?d=20120830');
	background-position: 95% -20px;
	background-repeat: no-repeat;
	padding-right: 2em;
}

I’ve also been having some difficulties working out how to filter the URLs to cater for my CDN setup, and for some reason the CSS didn’t seem to update when I edited one of the original files.