I don't think OGR will really change the contest much. We do still plan to trample /., right?? We won't be the only ones who might lose some power to OGR--so will /.
As clarified in the rules, this contest is about passing /. in the overall rankings on distributed.net RC5-64. Not in combined projects.
It seems unlikely that PhF flusher blocks could be revoked, but whatever, if anything, happens with the PhF should just be considered part of the suspense in this contest.