In the last year I've talked to five friends who have 8-12 year old boys. Every single one of those boys are Minecraft fans. The kids watch the Youtube videos, play with mods, skins, add-on packs and play with other kids online.
Two of my coworkers are IT professionals with decades of experience. Both of them have said that by the time their kid is a teenager, their son will be a far, far better Java programmer than they ever will be. Syntactically, it's similar to the C family of languages- like C# (Microsoft .NET version) and original C (Unix/Linux).
Minecraft is a great stealth edutainment product. At its core, it's playing with blocks or Legos on a computer. It's fun too! Some kids are okay with that for a day or a week or even a month. Some are happy with that forever. But every one of my friends' kids?
First you play with the blocks in the game. Then you learn that some blocks let you transmit a signal. Then you start making your own complex creations. Then you learn that it's possible to programmatically create something and have it appear in the game.
Your little friends start getting into it. You want to play together. You have to set up the network configuration. Someone has to set up a Minecraft server. Mom and Dad say nobody's setting up a server in their house unless it's properly secured and firewalled. Remember to practice safe networking, kids!
Then one of your group finds a really cool mod (modification to the program) online. Unless there's a one-click installation button (often there isn't), you need to install it yourself. Moms and Dads who don't trust completely unknown software distributions may insist kids install manually. Time to rebuild your Java libraries!
As long as they're installing a mod, the kids might as well make it do exactly what they want. They can modify the stats, make the fun stuff they want to play with in the game appear more often, or combine special effects. They can even use the techniques and concepts they saw in the original mod to make similar stuff on their own. Windows Notepad works, but it's easier to keep track of everything with Eclipse or Netbeans or something made for the task.
I don't think anyone has told the kids this yet, but now they're actually programming and writing code, on computers they've set up networks and firewalls for, in a language that forces them to use thought processes and learn concepts applicable to a wide range of IT and programming jobs.