No Man's Sky has game-changing day one patch. Farming added, base building on the way!

No reviews before release is usually worrying, but not always a sign that things have gone wrong. Now Hello Games has explained why No Man's Sky hasn't been seen yet: the day one patch adds a substantial set of new features and content.

I'll post the full patch below but here's a quick(ish) run though of all the things...

Totally changed the universe generation
More variety added to creatures, planets, atmospheres, moons, skies, terrain generation, ships, space station interiors (basically everything by the sound of it).
Inventory slots expanded on ship and player
Animals can now be fed, farmed and tamed (!)
Graphical, stability and balancing tweaks
Improved combat
You can now scan for discovered planets to increase the chance of meeting other players
There are now three 'paths' leading to different endings

That's a super condensed version mind. It sounds like Hello had a ton of stuff that it just couldn't get done in time to hit the retail release date. One practical upshot of this is that anything you've seen of the game played via leaked/early copies is no longer representative.

No Man's Sky update 1.03 patch notes

The Three Paths – there are now new, unique “paths” you can follow throughout the game. You must start the game on a fresh save, with the patch, as early choices have significant impact on what you see later in the game, and the overall experience.
The Universe – we changed the rules of the universe generation algorithm. Planets have moved. Environments have changed biomes. Galaxies have altered shape. All to create greater variety earlier. Galaxies are now up to 10x larger.
Diversity – Creatures are now more diverse in terms of ecology and densities on planets.
Planets – we’ve added dead moons, low atmosphere and extreme hazardous planets. Extreme hazards include blizzards and dust storms.
Atmosphere – space, night time and day skies are now 4x more varied due to new atmospheric system, which refracts light more accurately to allow for more intense sunsets.
Planet rotation – play testing has made it obvious people are struggling to adjust to this during play so it’s effects have been reduced further…
Terrain generation – caves up to 128m tall are now possible. Geometric anomalies have been added. Underwater erosion now leads to more interesting sea beds.
Ship diversity – a wider variety of ships appear per star system, and are available to purchase. Cargo and installed technology now vary more, and ships have more unique attributes.
Inventory – ship inventories now store 5 times more resources per slot. Suit inventories now store 2.5 times more per slot. This encourages exploration and gives freedom from the beginning. We’re probably going to increase this even further in the next update, for people in the latter game phases, and will allow greater trading potential.
Trading – trading is deeper. Star systems and planets each have their own wants and needs, based off a galactic economy. Observing these is the key to successful trading. We still working on adjusting this based on how everyone plays, but all trading values have been rebalanced across the galaxy, giving a greater depth. A bunch of trade exploits were uncovered and have been removed
Feeding – creatures now have their own diet, based on planet and climate. Feeding them correctly will yield different results per species, such as mining for you, protecting the player, becoming pets, alerting you to rare loot or pooping valuable resources.
Survival – recharging hazard protection requires rare resources, making shielding shards useful again. Storms can be deadly. Hazard protection and suit upgrades have been added. Liquids are often more dangerous
Graphical effects – Lighting and texture resolution have been improved. Shadow quality has doubled. Temporal AA didn’t make it in time, but it’s so close
Balancing – several hundred upgrades have had stat changes (mainly exo-suit and ship, but also weapon), new upgrades have been added.
Combat – Auto Aim and weapon aim has been completely rewritten to feel more gentle in general, but stickier when you need it. Sentinels now alert each other, if they haven’t been dealt with quickly. Quad and Walker AI is now much more challenging, even I struggle with them without a powered up weapon.
Space Combat – advanced techniques have been introduced, like brake drifting and critical hits. Bounty missions and larger battles now occur. Pirate frequency has been increased, as well as difficulty depending on your cargo.
Exploits – infinite warp cell exploit and rare goods trading exploit among other removed. People using these cheats were ruining the game for themselves, but people are weird and can’t stop themselves ¯\_(シ)_/¯
Stability – foundations for buildings on super large planets. Resolved several low repro crashes, in particular when player warped further than 256 light years in one session (was only possible due to warp cell exploit above).
Space Stations – interiors are now more varied, bars, trade rooms and hydroponic labs have been added
Networking – Ability to scan star systems other players have discovered on the Galactic Map, increasing the chance of collision. Star systems discovered by other players appear during Galactic Map flight
Ship scanning – scanning for points of interest from your ship is now possible. Buildings generate earlier and show up in ship scans
Flying over terrain – pop-in and shadow artefacts have been reduced. Generation speed has been increased two fold (planets with large bodies of water will be targeted in next update)
Writing – The Atlas path has been rewritten by James Swallow (writer on Deus Ex) and me.  I think it speaks to the over-arching theme of player freedom more clearly now. Early mission text has been rewritten to allow for multiple endings.