Braid is a tricky game to review, because when you talk about how appropriate it is, you mean something completely different from when you talk about a violent shooter or beat em up. In terms of inappropriate content, I think a 12 year old could handle the single use of the "B Word", and the implication of a relationship that started falling apart. But in terms of emotional depth...well, it was, at times, emotionally difficult for me to play at 25. Even in terms of sheer challenge of game play, it was difficult for me as well. I think that a very mature 15 year old, ready to deal with the issue of real, romantic love (They do exist...rarely) who is quite good at puzzles should be encouraged to play this game. But there's also a pretty good chance that they simply won't like it, and preferring a game that's a little more straightforward. So to most parents, you probably shouldn't buy this game for your kids, just give a go ahead if they are informed about what the game is, and specifically want it. But I think that, just maybe, you should consider buying it for yourself, because it is beautiful.
Best game out there. Hands down. The game has an underlying meaning that teaches us all important lessons for life. It also makes you think. There's no mindless shooting involved. You have to think outside the box for once. Hence: Educational value and positive messages.
Tim (the main character) is a fine roe-model. He is the example from learning from his mistakes. He thrives to make up for what he's done, but in the end ends up with nothing.
SPOILER: Please don't read if you haven't finished the game!
At the beginning of the game, if you read the books, they tell you the Princess is "being chased by a horrible and evil monster." In World 1, the last world, apparently, at the very end you discover it's the beginning. Where Tim's obsessions with the Princess started. Then the game plays the level reverse, and you see the Princess being carried off by the night. Braid turns out to the be "monster" the Princess if running from. Not only that, but the entire game was backwards! Literally.
There are many interpretations of what the game means. I think the moral is: Obsessions blind you from yourself. Tim never realized he was the "monster" because he was so obsessed with the Princess.
This moral also depicts that people who play it will become obsessed with finding its true meaning. Wasting their time, and not even realizing the moral is what's happening to them at that moment.
I didn't chose the bad language symbol. But they do mention the B word. (Now calm down! It's not a crime!) And anyway, the word is only mentioned once, in the epilogue. And it's in one of the hidden books that most players can't find.
So yeah, great game! :D