If you find yourself in the beta, you'll be able to play as a Trickster Rogue, Devoted Cleric, or a Guardian Fighter and have access to content up to level 30. Don't forget to take your companion and mount quests at levels 16 and 20, respectively.
You can kill the time until the beta's start by watching the game's new CG trailer. A (conveniently well-balanced) team of hardy heroes faces off against a dragon and an undead horde. Will they make it? You'll have to skip below the cut to find out.