A list of all changes (not just primary ones) can be found at
https://jdk6.dev.java.net/servlets/ProjectDocumentList?folderID=5790

My understanding is that there are no language changes in this release.  
If there are any, they should be minor (tweaking details of generics,
that sort of thing).  Major new APIs include a lot of XML and web
services stuff, the scripting API, and others.  See the API
documentation for details.

How about looking at the "What's New" tab of the link you posted?

Lee Weiner
lee AT leeweiner DOT org

Time to focus on Java 1.7.  The builds are at
http://download.java.net/jdk7/binaries/.  Build 02 (see
http://download.java.net/jdk7/archive/) seemed stable, but the current build
03 should be avoided.  Hopefully it will not be long before build 04 is out.

A bug in the Windows Look and Feel that makes buttons made of images
have negative width and height.

(OK, I'm teasing -- the same bug is also in 5_10 -- maybe a little earlier.)

Nasty bug, though. It seems, however, that if I setPreferredSize and
setMaximumSize to the size of the icon, the problem's taken care of.
(Yes, I reported it.)

Otherwise, it looks good, my application seems to start faster, and my
text fields are anti-aliased.