New behavior in scratch buffer in 21.1 and later

[Bingham, Jay]

I emacs 20.3, 21.1 and 21.2 installed on my Windows 2000 box.

Today while attempting to ad some conditional expressions to my .emacs files I 
noticed the new abbreviated display behavior in the *scratch* buffer.  This 
occurs when the result of the evaluation of an elisp statement exceeds about 
530 characters.  It appears that this was implemented in version 21.1.  At 
least it does not occur in 20.3.
I am not complaining about the new feature, I think that it is pretty cool.
What I would like to know is where can I find a definitive list of the new 
features that were implemented in 21.1 and 21.2.  I looked in the etc/NEWS file 
which purports to document changes since 20.1 and found no reference to 
"abbreviated display" and nothing about it in any of the entries containing 
"*scratch*".
Is this a bug in the documentation?  Are there are other features that are not 
documented?

J_)
C_)ingham
.    COMPAQ NonStop Integrity Systems
.    Austin, TX
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