How to select fields that appear on the social pane

Hi guys,

is there any logic behind how CRM Online selects the fields of each activity that are shown on the social pane?

For phone calls I have the fields: Call To, Modified by and something similar to Modified On (it does not show the exact date, just e.g. 'Today').

For appointment I have the fields: Subject, Due date, Modified by and again something similar to Modified On (it does not show the exact date, just e.g. 'Today').

And so on.

How can I determine which fields of each activity should be displayed on the social pane?

I would be very thankful for any help!

Regards