The Presiding Bishop has sent, and has publically released, a letter to the (so far, still) Episcopal Bishop of Pittsburgh and Moderator of the Network (and signatory of the Common Cause papers, as well). The letter seeks to recall Bishop Duncan to the discipline of the Episcopal Church, and encourages him not to support actions in the diocese to attempt to take it out of the Episcopal Church. You can read the letter here. I'm sure you can read reflections and reactions at all the usual suspects.
Some will see this as threat, certainly. Some will see it as insufficiently stern. I think the effort to write a letter with some sense of pastoral tone is largely successful, and largely worthwhile. I also think it's valid to begin with Bishop Duncan, since he's been so public a leader and advocate in the division within the Episcopal Church, even though other bishops have arguably moved farther and faster.
This letter isn't a surprise, nor, really, is its tone. There are some who have been calling for such statements, and for real consequences, for some time.
Still, I continue to be concerned about "abandonment of communion." I certainly believe the bishops in question wish to abandon the communion of the Episcopal Church. At the same time, what that means, and what that might mean as contrasted with abandonment of the the communion of the Anglican Communion, continues to be murky.
On the other hand, the Canons of the Episcopal Church are clear that violation of discipline (so, Constitution and Canons of the Episcopal Church); violation of doctrine (arguing that a diocese, even as the primary unit of the Church Catholic, can function out of the context of the larger Church that created it); and of ordination vows (which require assent to the doctrine and discipline of this church, and not of some abstract Communion) are clear and consequential violations. They should be sufficient.
We have sufficient clarity of definition in the terms of Title IV of the Canons of the Episcopal Church. We have sufficient evidence, I think, of violations less dramatic but just as important as "abandonment of Communion." If action is necessary (and few of us really think it won't be), let's stay with the concrete. As the central character in The Firm said, "It's not sexy, but it's got teeth."