Hellfire Citadel is the first winged dungeon in the Burning Crusade. It is the headquarters of the Fel Orcs in Outland, and is located in Hellfire Peninsula. Kargath Bladefist and his Orcs are keeping the injured demon Magtheridon captive and using his blood in experiments. It's kind of like UBRS, except split into three parts, and all the orcs are red instead of green. The Ramparts (mob level 60-62) features Watchkeeper Gargolmar, Omor the Unscarred, Vazruden and Nazan. The Blood Furnace (61-63) has The Maker, Broggok and Keli'Dan. The loot from the first two wings is about Molten Core-level, and you can come back at 70 and do them on Heroic difficulty for better items. The Shattered Halls (70) contains Nethekurse, O'mrogg, and Kargath Bladefist. The first three wings are all five-man. Magtheridon's Lair is a 25-man level 70 raid encounter in which you fight Magtheridon (sorry, he hasn't been killed yet, so no loot links!)
Coilfang Reservoir is another four-wing dungeon with three 5-mans and a raid instance. It's the home of Lady Vashj, leader of the Naga and one of Illidan's two lieutenants. It's also partially underwater. Gee, underwater and full of naga -- where can I sign up? The Slave Pens (mob level 62-64) contains Mennu, Rokmar and Quagmirran. The Underbog (63-65) has FIVE bosses: Hungarfen, the optional boss Tidewrath, Gha'zan, Musel'ek, and The Black Stalker, whose leggings I want already. Then, like in Hellfire Citadel, you go away for a while and come back at 70 for the other two wings. In the Steamvault (70), you fight Hydromancer Thespia, Mekengineer Steamrigger (not another Gnomeregan!) and Warlord Kalithresh, all of whom drop a ton of nice stuff. Finally, in Serpentshrine Cavern (70) you and 24 of your buddies fight Lady Vashj, who wasn't in the beta so we don't know much about her.
Auchindoun wrecks the otherwise beautiful landscape of Terrokar Forest. It is the headquarters of the Bleeding Hollow orcs, who tried to summon a demon but managed to wake up a ton of dead Draenei instead. The ethereal Mana Tombs (64-66) contains the giant voidwalker Pandemonius, the colossus Tavarok, and Nexus-Prince Shaffar. The Auchenai Crypts (65-67) house Shirrak and Exarch Maladaar, who drops very nice helms for rogues, feral druids and hunters. The Sethekk Halls (67-69) have Syth and Talon King Ikiss. Ikiss drops the key to the Shadow Labyrinth (70-72), which is populated by forces of the Shadow Council. Inside, you fight Ambassador Hellmaw, Blackheart the Inciter (useless ring incoming!), Grandmaster Vorpil, and the final boss, the primordial essence of sound, Murmur.
Getting tired of Outland's dungeons? Then head back to Azeroth, and back to the future, in the Caverns of Time. In the Caverns, you have to defend three key events in Azeroth's history from corruption by the Infinite Dragonflight. The first event, Escape from Durnholde Keep (65-68), sends you to Tarren Mill to help Thrall escape from captivity. Woo hoo, it's an escort quest! Along the way, you kill Lieutenant Drake and Captain Skarloc before facing the Epoch Hunter. Next, it's time for you to defend Medivh as he opens the Dark Portal ( 70) to ... uh ... help the Burning Legion invade Azeroth? Maybe you should just let the dragons change history this time. If you decide to intervene, you will fight Chrono Lord Deja, Temporus and Aeonus, who are all dragons. Finally, we have the 25-man Battle of Mount Hyjal (70), which has yet to be beta-tested -- which is kind of a good thing, because this is what that ridiculous raid attunement chart attunes you to.
By this time, you're about level 70 and can start doing the first available raids. But first, we have one last four-wing dungeon, Tempest Keep. Tempest Keep is in the Netherstorm and requires a flying mount to enter, so all of the wings are level 70 unless you really like having an all-druid party. It's the home of Kael'Thas and the Blood Elves. The first area of Tempest Keep, the Mechanar, has two levels. In the first level, you'll kill the gatewatchers Gyro-Kill and Iron-Hand to open an elevator and face Mechano-Lord Capacitus. On the second level, you'll fight Nethermancer Sepethrea and Pathaleon the Calculator. The Botanica has five bosses: Commander Saraniss, Freywinn, Thorngrin (nice druid staff!), Laj, and the Warp Splinter, whose dagger goes to me. Next, you can head to the Arcatraz and defeat Zereketh, Soccothrates, Dalliah the Doomsayer and the as-yet unlootlinked Warden Melicharr. At last, you head to The Eye and face the raid encounter with Prince Kael'Thas, which was .... say it with me, "Not Available In Beta."
Karazhan is the only ten-man raid available in BC, and it's for level 70s only. Karazhan is Medivh's old tower, and is likely to replace Naxxramas as the world's most mispelled instance. You get twelve, count 'em, twelve bosses to fight as you ascend the tower. This is also where you start seeing epics dropping. Quite a few of the bosses have known loot to link: Attumen, Moroes, the Maiden of Virtue, the Curator, and Terestrian Illhoof. Others, like the Shade of Aran, Netherspite, Nightbane and Prince Malchezzar, have complex strategies but few kills and thus little loot information. Malchezzar does drop the Tier 4 helm tokens. There are also three random plays that appear at the opera house, each of which becomes a boss encounter.
Gruul's Lair was the only 25-man raid encounter available in Beta. In the Lair, which is about the size of Onyxia's hideout and located in Blade's Edge Mountains, you face High King Maulgar and his council before fighting Gruul himself. Maulgar and Gruul haven't been killed enough for loot information, but according to WoWWiki, Maulgar drops the Tier 4 shoulder tokens while Gruul drops the Tier 4 pants tokens.
Black Temple is in Shadowmoon Valley and houses Illidan and his crew. This dungeon will not ship with the expansion, but will be patched in later. Illidan is reportedly the most difficult boss in Burning Crusade. Little is known about this instance, but the picture that accompanies this article was taken in a version of the final room of Black Temple.