It's a free to play WW2 flying simulator with difficulties ranging from arcade to full realism. Currently you can fly for Japan/USA/Britain/Germany/USSR, and they're still planning on adding ground/naval combat aswell but that could still take a while. The early levels for each country can be a bit dull as you're only flying basic (bi)planes, but as soon as you reach level 2-4 (depending on county) you open up some pretty fun airplanes. I definitely recommend trying this out seeing as it's free to play and easy to access through steam.
Its not great right now, its okay don't get me wrong, and its alpha/beta stage or whatever but I found it a very average game. Its going to be decent and well worth a play but if you are watching your bandwidth just wait for a few months till all is in place.
This is old news. Been playing since beta started a long, long time ago (over a year ago). Still has bugs to work out but other than that it's promising. Won't be up to quality for a few months.