Here's an unofficial English translation from the Vatican. And here's a translation of Pope Benedict's letter explaining it. And here's a little explanation from Whispers in the Loggia. I think this will be a positive (if not earth-shattering) change in the Church, and I hope to someday be fluent enough in Latin to celebrate a private Mass or two according to the 1962 form of the Latin rite.
Update: I read through the Pope's letter explaining the motu proprio, and it contains a lot of thoughtful insights, one of which I'll paste below for those of you not able or willing to read through the whole letter:
"There is no contradiction between the two editions of the Roman Missal. In the history of the liturgy there is growth and progress, but no rupture. What earlier generations held as sacred, remains sacred and great for us too, and it cannot be all of a sudden entirely forbidden or even considered harmful. It behooves all of us to preserve the riches which have developed in the Church's faith and prayer, and to give them their proper place. Needless to say, 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." [Emphases mine].