(5/31/11 The official English translation can be found here.)
From the address of the Holy Father to the participants at the Conference for the 50th anniversary of the Pontifical Liturgical Institute:
The Liturgy of the Church goes beyond this same "conciliar reform" (cf. Sacrosanctum Concilium, 1), whose purpose, in fact, was not mainly that of changing the rites and the texts, but rather that of renewing the mentality and placing, at the center of Christian life and of pastoral [activity], the celebration of the Paschal Mystery of Christ. Unfortunately, perhaps, even by us, Pastors and experts, the Liturgy was treated more as an object to be reformed than as a subject, capable of renewing Christian life, from the moment in which "there exists a very close and organic link between the renewal of the Liturgy and the renewal of all the life of the Church. ..."
...
The Liturgy, privileged witness to the living Tradition of the Church, faithful to its original objective of revealing and rendering present in the hodie of human affairs the opus Redemptionis, lives from a correct and constant relationship between traditio and legitima progressio, clearly expressed by the conciliar Constitution at its n. 23. With these two concepts, the conciliar Fathers wished to deliver their program of reform, in balance with the great liturgical tradition of the past and the future. Not rarely are tradition and progress contrasted in a maladroit way. In reality, both concepts complete themselves: tradition is a living reality, including therefore in itself the beginning of development, of progress.