THE BLACK TEMPLE: Already planning to strut around Shattrath in your T6 Raid gear? Don't bank that T5 set too quick. The Black Temple attunement quest is ... epic. And it hasn't even been fully discovered so far. What is known is that you will have to slog through a great deal of the Burning Crusade raid content that comes before it: Karazhan, Gruul's Lair, Magtheridon's Lair, Serpentshire Cavern, The Eye and The Battle of Mount Hyjal. And many of those raids require extensive attunement quests of their own. If you are still itching to begin, you can dig in with the Tablets of Baa'ri chain out of Shadowmoon Valley to start grinding that Ashtongue Deathsworn rep.
NETHERDRAKE EPIC FLYING MOUNT: First, don't confuse this with the Swift Nether Drake top Arena teams are awarded with at the end of every season. That one has a speed increase of 310% and has an armored appearance. This is the normal epic nether drake with a speed increase on par with other epic flying mounts: 280%. What's special about this epic flying mount is that it can be obtained through solo and small group quests. No raid required. What is required is a great deal of dedication.
The first steps on your journey is to dig yourself out of Hated reputation with the Netherwing clan and get all the way to Exalted. This is accomplished through solo, 5 man and 3 man daily quests. Head to the south east corner of Shadowmoon Valley and speak to Mordenai in the Netherwing Fields. A complete write up can be found here.