Soon all level 70 World of Warcraft players will be able to face against Illidan Stormrage, the demonic night elf of Warcraft III, in The Black Temple, a new 25-man instance that Blizzard is developing to include very soon.
Requiring 25 level 70 people and being the first non-linear instance makes it a very interesting addition, as seems that it will be the hardest one (probably that's why they allow to go directly to fight the boss if you want to do so).
I'm going to need to make a sacrifice of sleeping time in order to reach level 70 asap... I'm dying to see all the dungeons and instances :(