Specifically, the update provides proper support for Creative Labs' EAX technology, so that the game no longer produces "critical errors" when the option is activated. It also removes the blur that lingered on-screen after cutscenes and dialog choices.
In case you missed it earlier this year, those that purchased the original release of the well-received PC fantasy RPG can upgrade to the Enhanced Edition for free through a series of patches, which bring a revised script and more quests to the game.
I sometimes get that blur effect, sometimes. But I hope this fixes it. Great to see them still supporting the title and listening to their community.