The "'28 Book" was the standard Episcopal prayer book for almost 50 years. (Unlike many other Protestant denominations, Episcopalians follow the forms contained in the prayer book quite closely for almost all services.) The Book of Common Prayer is so called because it is used for prayer "in common" - i.e. in the body of believers. It contains the form of worship for Morning and Evening Prayer, Holy Communion, more specific services such as Baptism, Confirmation, Holy Matrimony, Unction of the Sick, and the Psalter (not King James but Cranmer's version). Later versions also contain family prayers and services for use in the home.
The first version was written by Archbishop Thomas Cranmer in 1549, and it has been revised many times since. The American '28 book was the only major revision of the prayer book since the American Revolution, but it still did not make any changes in the basic form or import of the major services (Morning & Evening Prayer and Holy Communion). That's why the '79 book raised such an almighty stink - it "modernized" the language and made major structural and doctrinal changes in the major services.
Hope that answers your question!
My priest told us that the CBP is always being worked on, updated, etc. for the NEXT revision. ARGGGGG