For one thing, the Introduction appears to have been completely untouched; there are no references to any publication after 1951 (with the exception of references to two recent compilations by the Opies), and most date from the 1940's (for example, the reference on p. 3 to "two admirable Presidential Addresses by Lord Raglan to the Folk-Lore Society, 20 Mar. 1946, and 5 Mar. 1947"). Moreover, the discussion evinces a strange English elitism that may have seemed conventional six decades ago, but has not worn well with time. For example, the Opies seem to consider it a great fillip to the status of nursery rhymes that some of them can be shown to have been written by respected members of the English upper class; but we would consider these figures second or third-rate authors today (for example, Sir Charles Sedley). Also, there is too much blue-blooded in-group banter; for example, under "Bo Peep," one finds this assertion: "it is on record that in his early days Irving played the part of the wolf in Little Bo-Peep at Edinburgh." OK, who is Irving? If you want your book to be read by the generations that succeed you, you must not make allusions that are comprehensible only to your peers and coevals.
Finally, the book is unnecessarily difficult to use. I STILL cannot find "Pop Goes the Weasel" in here; either I am an idiot or the indices are inadequate. I think the latter.