0 A.D. Alpha 9 has been dubbed "Ides of March" and features a new Roman Republic faction, a new combat system, a new trading system, new animations, AI improvements, and much more.
There's also a variety of minor improvements and improved FreeBSD support. There's also experimental Google Android support with a GLES / GLSL renderer. A fair amount of work is represented by this ninth alpha release as the last development snapshot was made available last December.
0 A.D. is officially available at this time for Windows, Linux, and Mac OS X platforms. In the announcement that Wildfire Games games sent out to the media, they shared they plan to have 0 A.D. into beta by late 2012.
More information on this new release or to download the open-source game, visit this Wildfire Games web-page.