Personally, I don't think this changes much of anything. Most parishes will see absolutely no change. So, it doesn't do anything to effect the average Catholic parishioner. But, what it does do is that it encourages those schismatic communities to reconsider unity with Rome. This is a good thing.
It was also issued with an explanatory letter in which much of the fear and speculation is put to rest. Before talking about this issue with others, please read both.
The USCCB has also issued a document that has 20 questions about the Motu Proprio. I will put some of the better ones below.
1. What is the purpose of Pope Benedict XVIs Apostolic Letter, Summorum Pontificum?
By this Apostolic Letter, promulgated motu proprio, the Holy Father seeks an interior reconciliation in the heart of the Church with those who have demonstrated an attachment to preconciliar liturgical forms, making it possible for all those who truly desire unity to remain in that unity or to attain it anew. Thus does he exhort the whole Church to generously open our hearts and make room for everything that the faith itself allows.
7. If a priest fails to demonstrate a minimum rubrical or linguistic ability to celebrate the extraordinary form, may he still celebrate the 1962 Missale Romanum?
No. In order to celebrate the extraordinary form, a Priest must be suitably qualified for and not prohibited by any impediments to the celebration of the Mass according to the 1962 Missale Romanum. This means he must have the minimum knowledge and ability required for a legitimate use of the extraordinary form.
8. As a rule, is it possible for a priest to abandon the ordinary form entirely?
No. The Holy Father states unequivocally that in order to experience full communion, the priests of the communities adhering to the former usage cannot, as a matter of principle, exclude celebrating according to the new books. The total exclusion of the new rite would not in fact be consistent with the recognition of its value and holiness.
14. Does the wider use of the extraordinary form of the rites of Holy Week reflect a change in the Church’s teaching on anti-Semitism ?
No. The 1962 Missale Romanum already reflected Blessed John XXIIIs revision of liturgical language often construed as anti-Semitic. In 1965, the watershed statement Nostra Aetate, of the Second Vatican Council then repudiated all forms of anti-Semitism as having no place within Christian life. When Pope Paul VI issued the Missale Romanum of 1969, the only prayer for the Jewish people in the Roman liturgy was completely revised for Good Friday to reflect a renewed understanding of the Jews as God’s chosen people, first to hear the word of God. Throughout his papacy, John Paul II worked effectively to reconcile the Church with the Jewish people and to strengthen new bonds of friendship. In 1988, Pope John Paul II gave permission for the Mass to be celebrated according the Missale Romanum of 1962 only as a pastoral provision to assist Catholics who remained attached to the previous rites, thereby hoping to develop closer bonds with the family of the Church. By this new Apostolic Letter, Pope Benedict XVI is merely extending such permission for wider pastoral application, but remains committed to the need to overcome past prejudices, misunderstandings, indifference and the language of contempt and hostility [and to continue] the Jewish-Christian dialogueto enrich and deepen the bonds of friendship which have developed.
19. Does this action call into question the liturgical reform of the Second
No. The Holy Father makes clear that the current Missale Romanum is the ordinary form (forma ordinaria) of the Eucharistic Liturgy. The extraordinary form is found in the 1962 Missal of Blessed John XXIII.