Arduino 0009 is now available:
Mac Intel: http://www.arduino.cc/files/arduino-0009-mac-intel.zip Mac PPC: http://www.arduino.cc/files/arduino-0009-mac-ppc.zip Windows: http://www.arduino.cc/files/arduino-0009-win.zip Linux: http://www.arduino.cc/files/arduino-0009-linux.tgz
Most of the changes are to support the new Arduino Diecimila, about which more soon. If you get a Diecimila, you'll need to download Arduino 0009, as previous versions won't work. Basically, under the hood, we've switched from using uisp to avrdude for uploading sketches to the board. There are also menu items for burning the ATmega168 bootloader with an AVRISP mkII.