UPDATE: The TAC ‘s website claims it is a union of 14 member churches with a total membership of over 400,000(!) worldwide.
From the good folks at the Shrine of the Holy Whapping:

I’m not sure how this will develop, but the implications are indeed sizable and very heartening. From Shrine reader the Bovina Bloviator’s blog:

The College of Bishops of the Traditional Anglican Communion (TAC) met in Plenary Session in Portsmouth, England, in the first week of October 2007. The Bishops and Vicars-General unanimously agreed to the text of a letter to the See of Rome seeking full, corporate, sacramental union. The letter was signed solemnly by all the College and entrusted to the Primate and two bishops chosen by the College to be presented to the Holy See. The letter was cordially received at the Congregation for the Doctrine of the Faith. The Primate of the TAC has agreed that no member of the College will give interviews until the Holy See has considered the letter and responded.

Particle upon particle. Momentum upon momentum. Glory upon glory; Like the snowflake become the avalanche, Lord, let it be!