Scientific Linux version version 5.4 is released for both the i386 and x86_64 bit architecture.
With the release of Scientific Linux 5.4 there is no need to add packages manually. There were some packages which were required but not present. This time, the packages are present and can be easily installed. The new release also supports the Atheros wireless chipset.
If you do not already know, Scientific Linux is a Linux developed by Fermilab, CERN and many universities and labs across the world. It aims at providing common productivity and development environments for research and experiment all over the world.
This year the release of version 5.4 also marks the five year anniversary of Scientific Linux. As seen clearly from the stats in this page, Scientific Linux has seen a big rise in popularity.
Scientific Linux is built upon Enterprise 5 Server and Client.
This page gives a detailed overview of systems on Scientific Linux has been installed.