Adam Beneschan expounded in
news:604b2e52-cfcb-49d0-9ecf-cf9f9135a57c@r19g2000prm.googlegr
oups.com: 

> On Dec 10, 12:13�pm, Warren <ve3...@gmail.com> wrote:
>> Dmitry A. Kazakov expounded

>> > All elder languages had capitalized names: FORTRAN,
>> > COBOL, PL, SNOBOL, C. ..
>>
>> That was once true of acronyms, but not for names. As a
>> name, it has never been right to fully capitalize Ada.
>>
>> Why they changed the rule for acronyms, beats me though. I
>> liked things they way they were. Did capitals get more
>> expensive? 
> 
> I'm curious---what acronyms are you referring to?  Most
> acronyms I see are still in upper case.  (A few
> pronounceable acronyms ended up becoming actual words, such
> as "radar", but that's an exceptional case.)  But I don't
> think there's been a rule change... 
> 
>                                 -- Adam

I believe I first heard about this change in capitalization 
from the publisher I worked with at the time (I wrote two 
Linux books and one Unix). I just took their word for it, 
since they were responsible for the "editing". 

The publishers were American (Sams and Queue, which are now  
now all part of the same parent company). FORTRAN and COBOL 
were originally acronyms and I believe COBOL still is. I also 
thought SNOBOL was an acronym but didn't look it up.

The Chicago Book of Style mentions it here. 

http://www.chicagomanualofstyle.org/search.epl?
q=acronyms&site=all&client=live&output=xml_no_dtd&proxystylesh
eet=cmosdev&filter=0&search.x=0&search.y=0&search_edition=16

You need a login to see the citation online. My hardcopy is at 
home, which I'll check if I still remember. 

Warren