I just upgraded from Confluence 5.1.3 to 5.1.5 and checked whether CONF-29036 is fixed in this version. In fact it is a lot better now especially in the tab section at the top. However, the icons to the right are still wrapping with large space descriptions (or small windows). Also there is no space between the icon on the left and the space description. See screenshot. For the icon wrapping I'm using the following workaround in the global styles.

div.spaceList div.icon-set {
	text-align: right;
	white-space: nowrap;
	width: 65px;
}