The Scientific Linux release notes are considered additive. This means that the one set of release notes, is meant to be added to the set below it. So the Scientific Linux notes, are changes that Scientific Linux did to the vendor's release. And the vendors update release notes are the changes that they did to the release before it.

Scientific Linux 6.4

SL 6.4 Release Notes
Vendor 6.4 release notes.
Vendor 6.4 technical notes.

Scientific Linux 6.3

SL 6.3 Release Notes
Vendor 6.3 release notes.
Vendor 6.3 technical notes.

Scientific Linux 6.2

SL 6.2 Release Notes
Vendor 6.2 release notes.
Vendor 6.2 technical notes.

Scientific Linux 6.1

SL 6.1 Release Notes
Vendor 6.1 release notes.
Vendor 6.1 technical notes.

Scientific Linux 6.0

SL 6.0 Release Notes
Vendor 6.0 Release Notes

Other Notes

CD/DVD Disk Image README's
README i386 CD/DVD disk images
README x86_64 CD/DVD disk images

Note: The above vendor release notes are provided {and copyrighted} by Red Hat®, Inc. The documentation is released via the Open Publication License (V1.0 or later).
Scientific Linux redistributes these original works (in their unmodified form) as a reference for Scientific Linux 6, because Scientific Linux 6 is built from publicly available, open source SRPMS, released by Red Hat®, Inc..
Scientific Linux is not affiliated with, sponsored by, supported by, or in any way associated with Red Hat®, Inc..