Just got it (the beta that is), and played for ten minutes. Tried to land on an island in order to build a command centre, but I have no clue how to do exactly that.
So far impressions:
1) I LOVE the launching of stuff. You are actually inside the carrier, and when you press "undock", you are either put into the water (the amphibic ATV kind of things) or put on the carrier deck (the hovercraft things) in order for you to launch. Wonderful.
2) so far, I love the map, where you can issue orders. I havent faced the AI yet, but it seems like it might be just as fun as Hostile Waters.
3) graphically impressive. but its a beta, so I dont know how feature complete it is. It seems overwhelming at the moment, but thats just because I dont know what stuff does.