It is a small but not insignificant recent change in written English that in Britain the newspapers have started spelling acronyms in lower case with capital initial instead of all in caps. The Universities and Colleges Employers Association and the the Department for Environment, Food and Rural Affairs are not UCEA and DEFRA, but (at least fairly often) Ucea and Defra. And in Times Higher Education magazine, the Higher Education Funding Council for England is now Hefce. This only applies to one of the two subclasses of what The Cambridge Grammar of the English Language chapter on lexical word formation (chapter 19) calls initialisms: it applies to the acronyms, not the abbreviations. Nobody calls the Science and Technology Facilities Council "Sftc", because you don't say "sftc" (could anyone?), you say "S F T C". Acronyms are more like words than abbreviations are, and the developing convention recognizes that.
By the way, as a couple of people have now pointed out to me, I ought to explain that as far as my judgments of what is a "recent" change in British English, your mileage may differ. I left Britain in July 1980 for a visit to the West Coast of the USA, and found it so enchanting that I refused to come back. From 1980 to 1994 I never even visited Britain. I worked as a professor at the University of California, Santa Cruz, learned plenty of American vocabulary and acquired post-vocalic [r], and saw very few British newspapers. I then moved to the University of Edinburgh in Scotland, and am still dealing with the language issues (there are words like chav in the newspapers now that I never knew at all). So when I say "recent" about British English, there is a strong probability that the recency illusion is in play. Recent for me is any time since 1980, because I've only just noticed it. For heaven's sake don't think I'm unaware of this: when I give my impression that something has recently been shifting or emerging in British English, you should take it with a large grain of salt and be prepared to give up to about 25 years of inaccuracy about dating of changes. Jesse Sheidlower tells me that British newspapers were at least sometimes spelling AIDS as Aids (notice, not aids, though — it's still an initialism in origin) before the end of the Reagan administration.
The blog Testy Copy Editors has discussed the issue. There zythophile notes the interesting example of VOIP: it looks like a word, but people say "V.O.I.P.", not "voip", so it is never Voip in British newspapers, always VOIP. It's an abbreviation, not an acronym.Posted by Geoffrey K. Pullum at January 25, 2008 10:38 AM