I believe that this revoke is just intended to Google, which represent a kind of treath, because otherwise why they wouldn't have revoked the VoIP iApps present in the Appstore Sipphone, 12connect, iNomado, Truphone.. Or was it the intention of Apple to let them in for a while and then to revoke them all? Why not.
But Apple is more intelligent than that and they probably are trying to find the good arguments to explain why Google Voice was "incompatible" with the Dev program..