Lord of the Rings Online Devs updated the official class page today with a more detailed description of the Guardian Class
Races: Man, Elf, Dwarf, Hobbit
'Go after those two young hobbits, and guard them. . . .'
-The Lord of the Rings: The Fellowship of the Ring,
"The Breaking of the Fellowship"
A doughty fighter and protector of the weak, a skilled Guardian can face even the toughest foes and survive. The Guardian is one of the few classes willing and able to try to draw more blows onto themselves, so they can retaliate with devastating maneuvers in response.
The Guardian will be the class of choice for players that enjoy drawing the attention of their foes in combat and taking advantage of their missteps. Masters of the defensive arts, Guardians use taxing attacks and irksome taunts to draw and hold opponents' attention, relying on their shield and weapon to turn aside incoming attacks with blocks and parries. A Guardian's combat style depends on creating openings during an opponent's attack to provide the opportunity for their own counterattack.
Finally! A class for all of the masochists out there! Not only will you draw that extra bit of pain and suffering to yourself but you'll look like a hero while you're doing it!