The Parish Book of Chant (PBC) is a handsome, inexpensive pew and
choir book. It is chiefly the work of Richard Rice, director of the Canticum
Novum Schola of Greater Washington, DC. (We can also thank him for
Communio, his collection of 110 Latin communion chants from the Roman
Gradual and the full text of the communion psalms—marvelous.) The notation
uses the older, “classic” Solesmes markings. At the back of the book
there is a seven-page tutorial on understanding the signs, melodies, style,
rhythms, and modes.
For comparison, there is only the Liber Cantualis (LC), the 118-page 1978
publication from Solesmes, in Latin only, unlike the PBC. Both volumes succeed
in providing a more than basic repertoire (beyond Iubilate Deo, 1974)
for singing chant at Mass. And, minus the propers, both provide for singing
the Mass in chant.
He continues on to mention that the real issue for music at the Mass are the propers, and he is right about that. His own efforts have done much to bring the propers to the people (using vernacular and plainsong) but the focus of this book is Gregorian chant. Also, this book sought to compile only the music for the people, and so the focus is on the ordinary chants and chant hymns.
The comparison between PBC is apt but I don't think he emphasizes the most important difference. Everything in the PBC has an English translation. The LC does not, and this fact alone was enough to limit the market for the LC in English-speaking countries. I can recall many years ago attending Mass at the National Shrine and using the LC, and, as someone unaccustomed to the Mass, feeling a relentless ache to know the meaning of the words that I was learning to sing.
In any case, he does offer a few criticisms, such as the omission of the Sequences. That was a tough choice but in today's parishes, do the Latin Sequences really constitute people's music? I've never heard anyone sing them apart from scholas. In a perfect world, of course, they would be in there, as would many other things. The omissions noted in comment boxes here would make two or three more books. But the point was to keep it small without driving up price and increasing weight.
Since it's publication in 2008, some 10,000 copies have been sold. That's a remarkable achievement. There is no sign that the pace of distribution is slowing. the reality is that this one book has done more than any in the postconciliar period to bring chant to the forefront, which is why it is used at the North American in Rome and many seminaries in the U.S., along with colleges and parishes. Here is the publication page. Here it is at Aquinas and More. You can also pick it up at Amazon.