Ok, here's a summary of how the questline goes.
You're attacking the 3 wings of the Frozen Halls, and somewhere along your journey, you discover the shatter remains of an ancient sword in the hands of your foe. You take the hilt you found to Quel'Delar's Rest in Icecrown. But a minion of the Lich King will try to stop you from using this blade in combat against Arthas, as she once used the blade as well, but shattered and spread the remains around Icecrown, being the reason you found it in the first place. You are then sent to Wyrmrest Temple in Dragonblight to gather more information from the dragons. After you do so, you are then sent to Dalaran in Crystalong Forest to talk to a powerful mage. You are then to obtain information on what the other faction knows about the blade you found. After you do so, you are to obtain a book for the mage you met in Dalaran. After you give him the book, you must enter the Pit of Saron and obtain 5 infused saronite bars, and defeat Forgemaster Garfrost for his hammer to begin fixing the blade. After you have done so it will then be time to enter the Forge of Souls to continue repairing the blade. And just when you think the blade is almost done, some disturbing presence around the blade begins pulling you toward the Halls of Reflection, the Lich Kings personal quarters, and also where he keeps Frostmourne when he's not wielding it. But be warned, Arthas sees what his blade sees, so make sure you do your business with Quel'Delar there before you attempt to talk with the spirits within Frostmourne. If you bring Quel'Delar too close to the Lich King's mighty blade, Quel'Delar will become corrupted, as warned by Uther, who showed up moments earlier as a spirit that actually managed to escape Frostmourne's icy grasp. Quel'Delar will then begin to attack you and your allies. You must now destroy Quel'Delar to regain control of it. But now that Quel'Delar has been corrupted, it has been weakened and cannot possibly be wielded by any man, no matter your steel or magic. So now, you are instructed to take it to the Sunwell in the Isle of Quel'Danas to purify Quel'Delar. But before you can do that, you need permission from the former wielder of Quel'Delar, who used it to defend what was left of Silvermoon from the forces of the Scourge. After you purify Quel'Delar in the Sunwell, the high elves and the blood elves currently in the Sunwell at the time try to claim the blade as their own. But the blade pushes them back, seriously injuring them. But one innocent bystander is accused of treason, for greed, for possesion of the blade for himself. But he quickly points out that Quel'Delar chooses who wields it. Quel'Delar is not just a blade, it is a conscience being. The blade then chooses it's wielder, you. Now, it is time to take the blade back to Icecrown to present it to your faction. Then, you are to present the blade to your faction again, but this time, you are to take it to Dalaran to recieve your final reward. But, your faction will not reward you with a weapon if you cannot wield a sword, so you then must take to the Argent Crusade at the Argent Tournament Grounds to recieve a mace of for you to combat your foes with. Quel'Delar, or one of the powerful maces are then yours to use as you wish, after all, Quel'Delar chose you.
Now, a lot of you probably noticed the summary was very, very long, and not very detailed. Well that's because I wanted to get the entire story in, and I only tested this on the PTR as a Tauren Druid, so I have no idea if the questline is any different for the Alliance.
Hope this helps, and if you are Alliance, this should still give you a pretty general idea of how this will go.
Oh, and I will be trying to get Might of the Faithful for my Blood Death Knight. I will be using it for DPS with Fallen Crusader on it. This will be a huge upgrade from my current weapon. My Death Knight is also a Blood Tank, but I am gonna try to get a weapon from either the new raid, or at least the new five man instances. And with Nerubian Carapace coming out as well in 3.3, maybe I can find some nice Tanking 1 handers to use.
Oh, and this blade looks epic!
Anyways, hope this helps you guys get your quest done.