Though IE8 has seen a steady increase in adoption since its launch, the latest numbers might have been boosted by a hole in IE6 that enabled the "Aurora" attacks on several companies in China.
Browsium, on the other hand, is a client-side solution that allows IT departments to configure IE8 or IE9 to work normally for most applications, but it can apply custom settings for internal webapps that were designed for IE6 or IE7.