I understand and agree with the general thrust of your 2nd paragraph there, though I wanted to chime in to say that I can attest first-hand it was pretty easy to prototype game ideas as far back as 1983, at least. I personally was doing it back then, in BASIC and 6502 ASM on the Apple II. There were even tiny indie shops back then making and selling their own games to the public. You usually found out about them from friends, or printed catalogs of distributors, or on BBS forums. In some ways, game dev has gotten "easier" since then, though in other ways arguably harder -- expectations are higher, there's vastly more competition both within games and across other media and other sources of entertainment on the web, and also the hurdles imposed by the App Store type middlemen.

Everything old is new again.

Everything old is new again. I second this with: fashion. If your understand clothes, you understand how fashion designers make old designs look new again.

In the actual implementation of Minecraft yes, regarding the concept i disagree. I'm no game designer, but I imagine that having a block based game with similar mechanics could be implemented a lot more "down to the metal". Procedural terrain generation has been around for a while, the crafting system is simple (maximum of 9 items => 1 item), and vanilla minecraft only uses less than 700 ids for blocks and items. Tool effects on blocks are relatively simple, and a lot of the other complexity can be done without (say rendering arrow flight paths or items dropped onto the floor). Which doesn't mean the current implemenation isn't somewhat cludged together, much to the chagrin of the modding community who don't allways appreciate coding decisions made within the vanilla game. We'll need to see how long the game lasts, since along with the development company Mojang being purchased by Microsoft, they don't always handle interactions with supporting projects such as Buckit, Forge or Cauldron too gracefully. Since they often rewrite and restructure portions of the game without providing the long promised modding API devs and modders have to completely rewrite their code between versions, which leads to high developer churn. There's lots of drama in the community, and Mojang is invariably connected to it due to several of the senior devs stemming from the community.

Do you think Minecraft and DayZ will last as long and become as successful as something like Tetris or Dance Dance Revolution?

DayZ? Probably not. Minecraft? Almost certainly. It seems hard to imagine a future where most of our children's children won't someday play something similar to Minecraft.

Minecraft should be ruled out. Infiniminer is the original. Does Tetris have any originals it was copied from?

I don't think you're going to find a lot of sympathy here, Mr. Barth.