It displays the child holiday days and sick days as well as photos that the parents have tagged them in from the News Feed posts.
You can add a new activity from the child's profile simply by clicking on 'new activity'. You then get a choice of registering naps, nappy changes, toilet visits, meals and sign in/out times.
The details that having been showing on the child's profile up until now, now show in the separate 'About' tab. This is split down into Basic info, Health, Sensitive information, Registration & Room moves, Permissions and Tags (shown below).
Further, there is now a 'Notes' section for you to add notes about that particular child.