Click on the Review button (in front of the Comments and Case Note buttons) when you want to see new activity on a case:
The start and end dates default to show the last 21 days, but you can edit the dates and search for a different time frame:
The activities shown are new entries for:
Case notes
Documents
Claim file notes
To-Dos
Appointments
Diagnoses
Contacts
Comments
Correspondence
There will be no entries shown in this window if any of these items have only been updated; only NEW items are shown.