Apple has been steadily beefing up its in-app purchasing policy to prevent children and adults from inadvertently buying items from within an app. As spotted by App Advice, Apple recently added a new disclaimer about in-app purchases to its App Store on the iPad.
The new "Learn More About In-App Purchases" page explains what in-app purchases are and how they work. Apple also gives tips on how to limit in-app purchases using parental controls.
You can find this page in the featured section of the iPad App Store, directly below the "What's Hot" section. There you will see a "Learn More About In-App Purchases" card. Tapping on it will bring up the full page.
Right now, this information is only available on the iPad. We assume it eventually will land on the iPhone App Store and the iTunes desktop version.