devkitPPC is a port of the GNU Compiler Collection (GCC) and includes a C (gcc) and C++ compiler (g++), a debugger (gdb) and associated utilities, with the architecture “powerpc-eabi”. It also includes standard C libraries based on newlib, which is specifically designed for embedded systems. Compilers and libraries are also included for the MN10200, the Matsushita (Panasonic) chip used in the Wii DVD controller. It is designed to be used in conjunction with libogc, a collection of Wii-specific low-level libraries.

Instructions for setting up the system are available for Windows, Mac OSX and Linux. Additional information and download links can be found at the devkitPro website.

Changes:

Update gcc to 4.4.1
Update newlib to 1.17.1 – please note this is not an official newlib release, just a snapshot we used to obtain some requested functions.
Update to gdb 7.0
wiiload is now version 0.5, this will require the latest version of the homebrew channel in order to upload code.
filesystem IO now defaults to unbuffered meaning that the full length requested on read/write is passed to the devoptab pseudo device drivers.
The powerpc-gekko prefix has now been replaced with the more standard powerpc-eabi, this will allow portable autotools based libraries to build OOB for devkitPPC. Users of the template projects will be unaffected.

http://wiibrew.org/wiki/DevkitPPC