It's in the nature of the case that any work of this type is partly out of date before it has got past the printers. A modest list of new entries is given at the start, and obviously some articles have been updated. Equally obviously, some others have not. At the time of the first edition in 1938 it was certainly true to say, as is said here, that knowledge of Handel was not advancing and possibly even declining. The revival of interest in his work was under way, but only just, at the time of Scholes's death 20 years later, but by the time of the tenth edition the transformation in that situation was well advanced, and one might have expected a drastic rewrite of that particular article. In other cases unexpected developments in our musical culture have caught the editors unawares. There has been, for instance, a remarkable increase in the recording of out of the way composers. The tenth edition has no entry at all for the 11th century abbess Hildegard of Bingen, no more than a one-line entry with cross-reference for Krumpholtz (contemporary with Mozart and specialising in music for the harp), but is rather better on William Kinloch, a composer of genuine stature I should say, who benefits from being included in an informative item on Scottish music. I own records of the work of all three, and got no help on two them from the Oxford Companion. One main purpose of a compendium like this is to provide easy access to basic data on such subjects, and if the revisers don't keep au fait with what is going on the volume will gradually become obsolete. That would be a matter of regret if so, because some of the more technical articles, notably as far as I am concerned the piece on temperament (aka tuning) and I am sure also the corresponding piece on tonic-sol-fa if I could have overcome my reluctance to wade through that tedious topic, are absolutely excellent. I got a sharp reminder of how quickly the situation can change when my eye lighted on an entry for `Glastonbury'. As I had expected, the cross-reference was to something totally unconnected with the great annual pop festival there. Whether the very latest update to the Companion has struggled to draw abreast of that I don't know, but if it has it will only be in time to be out of date again, as there's going to be Wagner as well as Will Young and the rest of them at Glastonbury this year.
Where the book also risks obsolescence is in some of the attitudes involved. Four major composers that I know of - Schubert, Schumann, Wolf and Delius - died through syphilis either directly or in a major contributory way. The subject is delicately avoided, and indeed in the case of Schumann the article reads as if the author didn't even know. Again, I'm not sure how well up he was in the final chapter of Tchaikovsky's life. For everyone's benefit, what really happened was that Tchaikovsky had been given an ultimatum by his former academy associates either to top himself or they were going to out him to the Tsar for his homosexuality. To treat this kind of thing as unmentionable in this day and age is just going to bring ridicule on a work that deserves better.
As I see it, the natural public for this book consists of comparatively well-informed amateurs, such as myself. What I find in it is some really excellent background material on a very good range of topics, and I'm all the way with Scholes in seeing the single-volume format as a basic requirement. It's not the job of a work like this to say the last word on anything in particular, although for all I know it may in many cases do just that. Keeping it up to date is important too, but I still recommend prospective purchasers to buy at bargain prices whether or not they are buying the very latest edition - it's not likely to make a great deal of difference. In many respects books are still a lot more convenient than the web is, not to say a lot more personal, and long may it be so.