We can't distinguish in the main view whether an item is accepted (approved or
contributed) or not (provisional or unconfirmed).
If an item has a warning, we also can't distinguish any of the acceptance
I suggest the following icons
Green Check - approved
Orange Check - contributed
Orange Question - provisional
Red Question - unconfirmed
The warning icon can combine with these.
For some ideas, see http://docs.google.com/Doc?id=dfqr8rd5_2crtp6wf3