One of the nicest things about the new GoldMines (keep in mind I've been around since 3.2) is the ability to add and remove columns from your Search Center. This is done on a per-user basis and is handled thusly;
Open your Search Center (i.e. start searching for a contact)
Look to the upper bar of the Search Center and click on the "Columns" button.
Then click the "Column Selection" tab.
Use the little arrow button to move columns to the right-hand side (which will now appear in your Search Center)
Ok your way out.
This is also a handy way to easily create lists; add the columns you need to the Search Center and then use the right-click Output To...Excel functionality.