SSPX to B16: We're REALLY just not that into you
In a failure for one of Pope Benedict's highest ecumenical priorities, it seems likely that the Society of St. Pius X--the Lefebvrites--won't be signing back up for full communion  with the Holy See. While a final letter from SSPX head Bernard Fellay is expected some time soon, two leaders of the movement have indicated they could not sign the document of principles the Holy See requires, which more or less says they accept the legitimacy of the Second Vatican Council.
With the 50th anniversary of the council's opening coming up, the pope won't have reunion with the SSPX to celebrate, despite the generous overtures he has made toward them, including the liberalization of the use of the pre-Vatican II liturgy. Luckily, one of Pope Benedict's non-negotiables has been Vatican II's recognition of Judaism, and the SSPX just can't accept the teaching that God's covenant relationship with the Jews continues.
The SSPX ceased being Catholic long ago, setting themselves up as a the church of the pure, the way the Donatists did so many centuries ago. In other words, they became sectarian--the true opposite of "catholic."
The departure of a few hundred thousand members is one thing; the departure of millions quite another. Let us hope that Pope Benedict might now turn to reconciling the 30 million disaffected Roman Catholics  in this country, or the 3 million in his own native Germany who have officially left the church by refusing to pay the state-collected church tax. Bishops there have decided to deny those Catholics access to the sacraments if they don't pay up--not, I think, the best approach.