I need to mine your knowledge about minecraft

It's totally, 100% kid appropriate. I can't think of anything possibly objectionable about it, unless you're a vegetarian. It's also a great way to learn about computers and logic, too, because there is something called 'redstone' in it that let's you build basically any kind of electronic circuit. It will almost certainly not run on a powerbook, though. I've got a brand new macbook air, and the performance on that is 'okay', but not wonderful. It's coming out on XBox very soon, though. I have to say, you might be missing a bonding opportunity with your kid if you just dismiss the idea of playing the game with him out of hand. Minecraft is a great game for kids and adults to play together at the same level. If you can get a server running in your house, you can build castles together, and monster traps and houses and basically anything you can imagine. Even if you're not playing at the same time. I'm sure you're going to hear a lot of stories about parents playing it with their kids in this thread. If you give the game a little bit of time, it's really a beautiful, thought-provoking game.

But in specific response to your #2, yes, you can easily keep your son offline in the "full" version of Minecraft, and have him only playing around in his own world, where he will not encounter other players (this is actually the best way to play it, if you ask me). He will be perfectly safe here, and you can even turn off the game's "nasties" (zomblies and skellingtons and such) if you're concerned about that.

I can't speak to computer stuff. My daughter plays on an old-ish laptop (almost four years old, or so), it's a bit laggy but runs fine. Does your son have friends who play? My daughter plays on a server run by friends of ours, with a bunch of other kids and the occasional parent of those kids. She LOVES playing with her friends, they're also often on skype, planning, chatting, building. And I love that she has a safe place to play and I don't have to watch like a worried hen. Playing with her friends definitely adds a lot to her enjoyment of the game, but I definitely wouldn't want her signing onto just any old server.

Single-player Minecraft has zombies and other creatures but you can turn these off and play it in creative (single player) mode, making it very kid friendly. In creative mode you get all the buildings blocks from the very start so it's super easy to get started. There's also a multi-player available and this would expose your kid to all kinds of people on the net. Probably the biggest challenge with Minecraft is figuring what to do with it. It's a sandbox where you can build anything but there are no goals, missions, levels, etc.

Just to add, I was playing on a 2007 Macbook Pro, and it was getting pretty laggy. I have an older Powerbook that is probably somewhat similar to yours, and no, Minecraft was not playable. The lag was almost impenetrable. The just too graphics intensive. It is, however, a great kids game. I introduced it to my friend, who subsequently introduced MC to his two boys (then aged 5.5 and 9) and they LOVE it. They play on single-player, usually on creative mode, and so they're not playing with other people. It's perfectly safe that way.

Also, the website has a free (much older version) of it available. It won't be good for actually playing, but it should provide a decent test of hardware specs.

Hope this isn't hijacking, but my 9 yo is into minecraft too and I haven't had time to do enough research to really teach her anything about how to build and how to play. Does anyone know of a minecraft video tutorial that isn't too boring for a kid (the one linked on the minecraft site is pretty slow). Thanks!

Your kid may complain that it's a far cry from the real Minecraft experience ( and he'd be right) but he still enjoy http://pixbits.wordpress.com/about/ which is a good attempt at recasting the Minecraft game feel in a 2D cartoony world for iPad/ iPhone both Junk Jack ( um except for some reason the main character possibly seems to be smoking a cigarette??? Hard to be sure - its very pixelly) and Minecraft ( setting aside to issue of interacting with other players in the networked multiplayer version) are kid-appropriate

My 11 year old is a big Minecraft fan. I would say the free game is absolutely fine, the youtube videos are usually not great (language, mostly, some drug references) although they are occasionally quite good and have some inspiring building projects highlighted. We got my son a low cost private server service that he can set to include a specific group of friends (knowing only their minecraft login name). Advantage: no strangers/adults in the space, and it is focussed on their 11 year old interests and skill level. We are letting him act as op and there have been some issues (of boys destroying each others stuff) which he has been able to handle, and that has actually been a good process. For a younger kid, if he has friends in minecraft, and you want to go the private server I'd say you would need to be the operator who sets controls and rules, fortunately this is very easy. Overall, I think it is a great game--generally positive experience with the community, lots of opportunity to be creative and original, not following a strict script in the game.