I'm pretty sure there had at one point been some exclusivity stuff. That should be pretty well gone at this point. Notch has left the company since they were purchased by Microsoft. I pretty much played Minecraft for one solid year, the only reason why I stopped was issues with the people that ran our servers. Shyguy and I used to play regularly. It is an extremely social game.
When I started playing it, there was no survival mode. You didn't have to eat to stay alive. Eating to stay alive adds some extra play mechanics. But lets start and explain how Minecraft evolves to the player.
You start off with Nothing. No items in your possession. Night time is fast approaching, if you don't take care of your business soon than the zombies will come out. You have to make a shelter. If you don't you will surely be devoured by the undead.
Well you get your shelter done, you wait out the first night and then you can work on being more diligent. You can build a more comfortable place so that its easier to survive. But now you want to make some fancy stuff, well, you're going to have to work for it.
I start digging. I want castles made out of diamonds, so this is going to take a while. One thing that happens is you dig down and then you discover there are elaborate cave systems. The problem with digging down is you have to have an ample source of light. If you don't create light than Zombies and skeleton bowman start spawning.
At this point, unless you cheat and look online you don't know anything. Its much more fun to experiment on the crafting side than to look it up. I spent a lot of time digging for coal. I need them for my fires. I want good clean stone and glass. Mined coal is better than coal made from plants.
Eventially you construct a huge castle, an elaborate mine system, a garden of apple trees. You're set.
Next step. Meet people online.
This is where it gets really fun. If you go on a good server there are lots of people building their own projects. It can be fun to just walk around and see what people have built. I started in a valley. This valley eventually became Permville. Shyguy was around to see it grow from shack in the middle of the woods to the megacity that it became. It basically offers you the freedom the Pioneers had when they were constructing their first city.
So, you build a huge town, well you're not the only one doing that. Then you build a railroad to link towns. You have people move into your city, you tell them where they can build, they build towers and their own castles, and brownhouse subdivisions.