Current status, and most likely the case for another year or so, is that its still essentially a playable tech demo. If you're looking for a new game to buy, SC isnt it, not yet.
What we have:
A 'small' (comfortably millions of kilometers) map with about 10 points of interest, small missions which IMO arent indicative of what the final game will have, they're just basic places to draw people to, create conflicts and give people and idea of whats possible.
We have seamless movement from the moment we spawn on a space station to requesting our ship, going outside to the open landing area, taking off, 'warping' 300-400k to a location, flying up to that location, EVA'ing (getting out of the ship and flying with suit thrusters) down to the location and so on, all without a loading screen or similar. The 'warping' is legit too, its not common but you can actually see people thousands of KM away travelling, they're like shooting stars going between 2 locations. So its actually happening, rather than removing you from the area, loading the destination, then dumping you in.
We have multi-crew ships in now, many of their mechanics are missing (ie cargo stuff, refuelling etc), but you can pilot while your mates sit in turrets, or they can mess about running around the ship.
Theres also a dogfighting mode (PvP), Vanduul Swarm (vs AI) and free fly for practising things.
Noticeable things missing:
Efficient network code is the big one currently, every single object is being calculated and then decided if its worth rendering it on your end, so a ship blows up 1m KM away, you suffer, a ship moves, you suffer. Its the CryEngine, its designed for deathmatches on small maps, and the ships are infinitely more complicated than player characters (and those ships have ppl in them too). They've been working on the long term solution, but its not really something you can iterate on bit by bit and improve in small steps, not without an initial big change.
After that its obvious things like more of everything. More ships, more landing zones, more planets & systems, 'wormholes' between them, game mechanics like mining etc (which arent going to be a matter of holding 'E' and having items appear in your inventory).
Squadron 42
Thats '2016' as of their statement almost 9mo ago, personally it felt too soon to be likely, but they've always been secretive with SQ42. However if the persistent universe (online) is any assessment of some elements of the game, theres quite a few things which dont feel ready. The way it'll likely unfold is around Nov they'll likely say its not ready, and we'll see it next summer.
The problem they have is this will be the first proper release of something, they delay it to make sure its solid, they suffer. They push it out too soon, they suffer.
Hows it coming along?
Thats a more positive topic, theres plenty coming along, it just isnt going to be at the pace that most people will accept, largely because its complicated and they're changing the cryengine to allow this stuff to happen, because there isnt an engine that comes remotely close to what they need.
Take a look at this:
Mainly the first 2 minutes, and if you dont want to watch it in full, jump to 9m00 and see them fly a ship from a space station down to the planets surface.
We have a sample landing zone, we have open space. At the moment those 2 arent connected, you have to leave one and then load the other. Eventually we'll be able to link the 2 using the above process. Developed planets will have their air traffic control and flight paths in, but lesser inhabited planets you'll be able to land anywhere, get out and walk or rover around. All seamless.
Whether the game will be fun in the end, who knows, but the technical stuff is coming together and the 'fun' is going to come down to balancing how things are implemented.
I mentioned mining earlier being more than a button press, but to give a duller example we know of, commercial passenger ships, rather than simply flying 50ppl from A to B safely, theres more to it if you want to be popular and charge more per seat for your services as a result. There are 'mini games' which a player or NPC can see to, and while mixing and serving people drinks might seem incredibly dull, they're taking the act of flying people from location to location (which needs to exist as part of the game, and we can do it if we wish to, as with pretty much everything) and making it about more than just flying, they're making it involve something more. When you apply the same attention they've given to a 'dull' job, and apply it to exploration, mining, bounty hunting etc then IMO the idea of being a miner in SC becomes more than going next to a bit of rock, pressing a button, and getting materials. It'll require thought, and reward people doing things carefully and correctly.
I think that's enough waffle to give you an idea though. If you have questions about any of it, or other stuff, ask away.
