Ok, here's the spiel.
You will see an 'Install' on your panel in Steam/Library/Games/Aerofly 2. When you click that, you will get a 10 Gig system update. Pretty massive. You will also then be out of the Beta and into the full version. I do not know what that means, except that that is what IPACS are saying in a post about the updates and release of the DLC. You need to update your Aerofly 2 to get the new DLC.
The DLC (free upgrade of high resolution regions around airports, bigger then it was before), is about 60 Gigs approximately. On my computer, its 85.4 for everything. I am at 34 Gigs now of the entire download.
Big updates...

This should be really interesting.
Its too bad you cant have the entire world in high rez. Just three states being 85 Gigs is quite a bit, and I imagine the full package (full download) is now up to 95 Gigs, roughly and approximately. Thats only 3 states in the USA. I wonder if they are doing a slightly better resolution world wide, like they talked about? That would be nice.
We shall see..