Bohemia Interaftive has just released a new patch for the ARMA 3 alpha which adds new features as well as ton of fixes.
Updates in this version include a new fog technology, adjustable sidearm stances and further stability fixes. There are a few other changes worth pointing out too, the sprint speed has been decreased, MH-9 chopper fuel gauges are fixed and they now carry more troops, and this one is super important for all players, fish no longer only swim north.
The update is now live on Steam weighing in at a 380Mb and you can still join the alpha test by ordering on Steam. Check the full patch notes now on the ARMA 3 site.