The "My Account" page has now been reorganized a little to put the growing number of options in more sensible locations.
If you don't find the setting you're looking for on the main "Online Registration" settings page (which used to be REALLY TALL!), just look on the other sub-pages, such as "PayPal Account Settings", "Discounts and Fees", and "Returning Players".

Just remember: After you click "My Account" on the menu at the left, You next have to click "Online Registration" at the top of the My Account page, and then these additional pages will appear (also at the top, just under the menu line containing "Online Registration".)