Tricky question.
Here's my understanding on this ...
The only people who can participate in PAB are those individuals
appointed by organisations who have signed the gTLD-MoU
I think when POC offered observer positions, they did this on
the basis that the observers would in fact be PAB participants.
I would expect that if PAB appointed somebody other than a
PAB participant (appointed by a gTLD-MoU Signatory) POC
would reconsider these observation roles.
regards
Peter Mott
2Day Internet Limited.
http://www.2day.net.nz