Tapping on the "Email Captures" button on CleanUp Duplicates app's home screen will display a list of the new contacts to review. If the contact is flagged as "New info", then it is a contact that does not currently reside in your contact list.
If you wish to select multiple at once, press the "Select" button in the upper right corner. Following that, press on the contacts you wish to select. Once you have selected the contacts, you can press Ignore or Save at the bottom of the screen to take action on those contacts.
If you wish to review the captured signatures one at a time, press on a contact to review it. For existing contacts, the new information captured is highlighted and presented with the information you already have for that contact.
Buttons at the bottom allow you to Ignore or Save the changes/new contact.