Sure Red Hat Enterprise Linux 5 is a stable distribution, but that doesn't mean that it doesn't change and improve - even inside of release cycles.  Case in point is Red Hat Enterprise Linux 5.2 (RHEL) now available as a Beta.

The 5.2 release is the second incremental release since RHEL 5 was released in March of 2007 (RHEL 5.1 Beta appeared in August of 2007). With the 5.2 release Red Hat is adding virtualization enhancements including the ability to handle a 64 CPU system.  Additionally the critical 'libvirt' technology which helps to manage the virtualization instances now gets remote management support.

IPv6 support also gets a boost in RHEL 5.2 with the addition of a DHCPv6 client and server (regular DHCP doesn't quite handle the longer IPv6 addresses all that well).

Red Hat has also improved on a long list of driver and architecture specific improvements in the 5.2 Beta. 

A Beta is also a great place to try out new technology as well and that's where the 'Technology Preview' components come into play. Among the preview items in the 5.2 Beta is Trusted Computing Group (TCG) / Trusted Platform Module (TPM) Support. TCG/TPM is often a requirement in high security and government deployments and having it baked into the regular mainstream version of RHEL is likely to be very attractive for allot of potential customers.

Red Hat expects the beta testing period for Red Hat Enterprise Linux to continue until May 7, 2008