Arena Commander was released at around 2pm SG time (GMT+8) on Wed 4th July 2014. The download was 10 GB in size. I finished downloading Arena Commander yesterday evening and took my Aurora for a spin. The keyboard and mouse controls felt a bit wonky but I quickly read that people had found it easier to fly in Relative mode by pressing Ctrl-F, as well as to turn off G-Safe and COMSTAB. I did this and managed to survive to wave 5 in the Vanduul swarm mode. I'm thinking of purchasing the Thrustmaster T16000 joystick to have a go at being a fighter jock.
V0.8 of Arena Commander comes with 2 maps, Dying Star and Broken Moon. There are two modes of play - Free flight mode and Vanduul Swarm. There was a sweet bonus as well. CIG released a PDF manual of Arena Commander as a reminder of the glory days of Wing Commander: Arena-Commander-Pilots-Guide-V0-8.pdf. Below are the screenshots of the launcher downloading the Arena Commander install.