Damien Thompson has highlighted the letter and quoted Fr Z in his post "An atrocious letter from Leeds" on his Daily Telegraph blog "Holy Smoke". Fr Ray Blake has his own observations, and Catholic Action UK have suggested "local action as appropriate."
The letter raises a number of serious issues that merit discussion (some have already been discussed extensively here and elsewhere.) I hope to find time particularly to look further at the question of the way in which the two forms of the rite can, as Pope Benedict said, be "mutually enriching." It does not seem to me at all "clear" that there is to be no transferring of elements from one form of the rite to the other. There is talk of adding some newer prefaces to the older rite. I can see no reason not to restore some elements of the older form as options for the Novus Ordo.
There is one point made by the Holy Father that deserves more attention. In the accompanying letter to Summorum Pontificum, he said,
"The present Norms are also meant to free Bishops from constantly having to evaluate anew how they are to respond to various situations."This struck me as a very sensible point. I always felt that it was pointless extra bureaucracy for the Chancery to be issuing permissions for funeral Masses etc. Now that the Motu Proprio has freed the Bishops from this, it does seem odd that some Bishops seem be creating a whole lot more work in intensively "moderating" the classical form of the rite.
In the meantime, there is a very encouraging report from Orbis Catholicus: Summorum Pontificum: the Rome update. There is now a daily Mass at 8am in St Mary Major's in the usus antiquior, celebrated by one of the canons of the Basilica, many altars in Rome are seeing the return of their altar cards, indicating that more private Masses are being celebrated in the older form of the rite.
If you really want to know what is going on, a good way to check is to look in the shops on the Via Conciliazione. Apparently they are now selling new hand missals for the laity, printed in Italy.
Oh, and the 1962 Missal is listed in the new publications section of the Vatican Press.