Following up on the letter from William Nye to TEC, the actual proposals to come before the General Convention in July were the subject of analysis by Andrew Goddard, earlier this month (I had missed his article until today).
An article, written from the perspective of one of the TEC bishops opposed to these changes, can be found here: Reconstructive Surgery on the Prayer Book? by Bishop Dan Martins.
And yesterday, there was This Source of Doctrine and Unity Requires Our Care by Bishop John Bauerschmidt.
Scott Gunn has also written about this proposal: Study of Marriage.
Bishop George Sumner has issued a pastoral letter on the same subject.