The CentOS project welcomes you to CentOS-5.4.
The complete release notes for CentOS-5.4 can be found online at http://wiki.centos.org/Manuals/ReleaseNotes/CentOS5.4. A list of frequently asked questions and answers about CentOS-5 can be found here : http://wiki.centos.org/FAQ/CentOS5.
If you are looking for help with CentOS, we recommend you start at http://wiki.centos.org/GettingHelp for pointers to the different sources where you can get help.
For more information about The CentOS Project in general please visit our homepage at http://www.centos.org.
If you would like to contribute to the CentOS Project, see http://wiki.centos.org/HowToContribute for areas where you could help.