Description on amazon says
Each year, changes occur to an estimated 15-20% of North America's roads and highways. That's why BMW offers annual digital road map updates for your on-board navigation system. It includes Millions of new Points of Interest in 100+ easily searchable categories. Categories include necessities such as food, gas, and lodging, to attractions like shopping malls and museums. Vehicle must be equipped with CD or DVD based factory installed navigation (option SA 609).
So I'm guessing its just a general update. I would like to get my hands on this but I can't pm yet :/
I would suggest pming mrbones from the other nav thread and see if he would want a copy to upload.