I think that the profusion of books on Tolkien are a sign of the times.
I was thinking the other day about how 15 years ago our newspapers had news in them, and how celebrity stories were only found in the Sunday tabloids, but today all the papers are stuffed full of celebrity stories - even the broadsheets had front pages about Macca's divorce. It's because we've slipped deep into celebrity culture. This has had a big effect on the publishing houses as they seek t fill Waterstones with ever more biography and autobiography. Geri Halliwell has written two already and we are facing the prospect of one from Chantelle, the noby made famous by going on Celeb Big Brother a few months ago!
Tolkien is not exempt from this. We are
fans, and what's more, we are pretty rabid, obsessed fans. So the publishing houses know that a new book on Tolkien will
sell. So they publish them.
I can't help thinking that anyone wanting an academic career would do well to get into Tolkien as they will soon become a mini-celebrity themselves, attracting large queues for book signings at Tolkien conferences, and supplementing a meagre academic salary in the process. Much better to get into being a Tolkien scholar than becoming an expert on obscure 19th century chapbooks or somesuch.