Protestant readers might be interested in this quotation from a 1994 interview with George Lindbeck, one of the Protestant "observers" in attendance at Vatican II.
I would think that Ratzinger's ecumenical views are ... weighted by his disappointments with what has happened on the non-Catholic side. He clearly wants to avoid a doctrinal permissiveness that implies that church doctrine is unimportant, or a kind of pluralism that makes all churches doctrinally equal. He insists that this is not the way to read the Council. And I wouldn't disagree with that.
My guess is that Ratzinger thinks the time is not ripe for a definitive ecumenical articulation as long as the Roman Catholics don't have their house in better order and as long as non-Roman Catholics are incapable of communally authoritative teaching or decisions. This is my own interpretation, to be sure, but I think his view is that as long as the churches on both sides are in such immense disarray, the time for clarity about "reunion" has not arrived.
If Pope Benedict is going to delay ecumenical moves "as long as non-Roman Catholics are incapable of communally authoritative teaching or decisions," he's going to wait a long time. It seems unlikely that this Pope will make any strides towards Christian reunion; but it would have been foolish to suppose that any other candidate would have done differently. Ecumenical advancement and understanding must continue at the lower levels, even if only at the interpersonal level, since any move towards union, however limited, of structures and worship at the macro level is now deferred indefinitely.