An Orthodox monk I know has expressed the view that those Continuing Anglican groups that have dropped the filioque are the only Western confessions worth the bother of an ecumenical dialog.
(In fairness, this view was expressed before the election of Pope Benedict--if the Latins have three or four more like him, dialog with them is definitely worthwhile, too.)
What if dialogue leads to dropping the filoque? And where does the dialogue go after that?