As far as I understand it (which is not very far) - there would be no point in simply withdrawing PTS now (after the Dec 14 snapshot) since Cryptsy would just send the old (worthless) PTS to a new external address, and worse might discard the original ownership address from which new PTS can be claimed.

^^Is this right?

If so, unless Cryptsy are prepared to undertake the migration on behalf of all users (which i doubt for the reasons in the OP) I will need to convince them to send me the address and private key, then load it into the new wallet client running the new blockchain fork.