I have a couple machines running 5.6 fully updated from cr repo.  When I did 'yum update' this morning it found 8 updates:
       centos-release-5-7.el5
       centos-release-notes-5.7-0
    ghostscript 8.70-6.el5_7.3
    nspr 4.8.8-1.el5_7
    nss 3.12.10-4.el5
    nss-tools 3.12.10-4.el5
       ntp-4.2.2p1-15.el5
       initscripts-8.45.38-2.el5

However yum reported 404 on everything but ntp and initscripts.  I installed ntp and initscripts individually and yum continued to report 404 on the rest of the updates on both machines.  One machine i386, the other x86_64.

I did a 'yum clean all' followed by 'yum update' and it installed centos-release and centos-release-notes but not nss, nss-tools, ghostscript or nspr updates.

[]# cat /etc/redhat-release
CentOS release 5.7 (Final)

[]# rpm -q nss nss-tools ghostscript nspr
nss-3.12.8-4.el5_6
nss-tools-3.12.8-4.el5_6
ghostscript-8.70-6.el5
nspr-4.8.6-1.el5_5

Both machines had identical results and appear to be fully updated to 5.7 but with at least four packages not updated.  I don't think this is an intended result.

Any thoughts much appreciated.

B.J.

CentOS Linux release 6.0 (Final)