I've had Minecraft PE on my phone/tablet, which I mostly play in creative mode (the controls are awful for reacting and moving quickly) every now and again, when bored.
However a couple of weeks ago I decided to jump in and get the "Real thing"; buying the java client for laptop/desktop.
It's fun, but I was shocked at how bad the server eco-system is: There is 1) The official server, which I use, but I am very worried about making it accessible from the internet. I'd feel like I'm putting a rabbit on the motorway, and hoping it doesn't get run over. Then there is 2) Bukkit, which tries to add features that make running an internet accessible server more feasible; but the project has been killed. (Majong hired some key developers and then shut the original down); next I found 3) Spiget, that is a clone for (2) the one of the community keeps alive. Finally 4) you can "rent" a "realm" from majong, basically paying them a monthly fee to run a server for you.
All these servers appear to become daemons by running a jre in GNU Screen! With various scripts that execute commands to the "server" via screen cli echos. Other functionality works by just copying key files around. I guess such Rube Goldberg server setups matches the in-game way of doing things
And I though Banking application web servers were terribly put together...
I had thought that after so many years, and money that the server side things would be rock-solid, and these days it would just about adding new things to play with in the world.
I'd expected a something near to a proper DB for the world data, with methods like transactions to prevent corruption; audit records that let you roll the state of a particular area or thing back to some previous state. Or the ability for users to claim (or be assigned) an area, that only they can break, but others can visit. Maybe a set of reasonable tools and features to identify and deal with misbehaving users, either via their own in world action, or via "modded" clients.
If you think I am being paranoid, search for "minecraft griefing", e.g. on youtube.
Despite all that I would still consider making my server internet accessible, probably only to people I know IRL. (Not to say my server is something special, that would be of any interest to anyone. Its of interest to just me, because its "my world")