If you're one of the lucky players who got in this week or if you manage to get in in the next few weeks, there are some important facts you should know before you play the beta. For seasoned veterans of beta testing, these will be self evident. For the others for whom this will be the first beta ever, these are things you should read and consider. If you don't, you could turn into one of the disappointing trade chat trolls who rages about their warrior suddenly having a mana bar (and other fun beta mishaps).
Oh yes, there will be bugs
Above all else, the thing you can most expect from the beta of any video game ever is that there will be bugs. Bugs are one of the main reasons games go into beta; they're a way of allowing scores of players to scour every inch of the game world for bugs by doing everything possible that could possibly cause an issue. By doing this, Blizzard can isolate and treat bugs before they ever make it to live servers, allowing players on live a smooth playing experience.