This page discusses the relevant changes introduced in CRUX 2.3. Everybody upgrading from the previous release is advised to carefully read the following notes.
CRUX 2.3 includes glibc 2.5 and gcc 4.1.2. GNU lists glibc 2.4 as the stable release, anyway we have not found problems with version 2.5, which is used by other distributions as well.
The monolithic x11 package has been replaced by the new modular xorg distribution. As the results of this update, crux.nu now hosts a dedicated "xorg" ports repository, installed by default. Ports are available under /usr/ports/xorg, you may need to add this location to you /etc/prt-get.conf file if upgrading.
the netkit-base port has been replaced by inetd and iana-etc. We currently not use the whole set of services/protocols listed at http://www.sethwklein.net/projects/iana-etc/ , while keeping the name for future compatibility.
By popular request we included iproute2 and iputils in the core collection. The new default network script /etc/rc.d/net has been updated to use /sbin/ip instead of the traditional ifconfig and route commands (still available and installed by default).
Important: when upgrading from CRUX 2.2 an /etc/rc.d/net script based on iproute2 is installed, a backup copy of your previous version is saved in /etc/rc.d/net.orig. Be sure to adjust /etc/rc.d/net after upgrading.