oh yeah that video made me get arma a few years agowhy not? is it better?
I'm wondering because I have it but I haven't played oa yet
OA basically doubles Arma 2's content with a 20 dollar DLC. It adds around 4-5 new factions, 3 (?) new terrains, an unhealthy amount of new weapons and vehicles
and unrestricted access to all additional DLC content with lower quality textures so as not to fragment the community.
I also redoes the vehicle health meters (ditching the graphic in favor of a more discreet color system), tightens up the hud (removing those ugly green boxes in the video) and expands mod support.
The OA content is so good there is a team of modders that are working on importing every Arma 2 asset over into Arma 3 in a project called CUP. So far they have almost all the weapons in.