
Just got mine in the mail today. I read the article, and it really clears things up.
There is no blood in the game, nor are there any guns or similar weapons. Instead you use slingshots, wedgies, marbles, and other schoolyard tools. Also, the game is far more restrictive than GTA. In GTA you can walk up to anyone and just attack them, and even start a huge NPC massacre. This isn't possible in Bully.
If you violently attack other students with the more powerful melee weapons like bats, they break after a couple hits. Also once you violently attack students, the prefects will rush in and detain you, thus sending you to the principle. Although Game Informer detailed this very carefully, I'm willing to bet that there's going to be a code or "mod" that'll allow you to attack students at will, creating another Hot Coffe-esque uproar. -_-
The game's system is based on time management. Each day is split into various segments, like a real school day. So at certain times you'll be expected to be in class (chemistry, english, gym, etc). Of course, you can skip classes all you want, but it'll hurt your character's growth in the game. Classes increase your skills in various areas. For instance the more you participate in English classes, the easier it will be for you to talk your way out of possible detentions.
Classes seem to have heavy minigame elements. It'll be interesting to see how people react to them. Generally people don't play GTA for the story; they play the game to cause mayhem in the world. This isn't really that possible in Bully, so I wonder if it could turn some people off.
Also another cool thing is the respect system. The school population is divided into various cliques; Bullies, Preps, Nerds, Jocks, and another group that's into cars. You gain respect from each group by helping them out with various problems. So if you help a Nerd by accepting his plea to get his Magic cards back from a bully, your Nerd respect meter increases while the Bully meter decreases. Pretty cool.
Stealth is also incorparated into the game. One mission decribed a scenerio in which a rather seedy teacher asks you to help him get back some of his "laundry". In reality this "laundry" is really a stash of panties from the girl's locker. You have to sneek into the locker room while avoiding the prefects/teachers, and then escape to the teacher's house with the loot. Sweet!