Tactics progression in Burning Crusade?

After listening to the latest Farm Status, I started to wonder about the tactics and coordination required for Burning Crusade endgame raid instances.

Currently the level progression, tactics progression and gear progression goes hand in hand when you go through the game. The first instances are fairly simple and require only basic coordination to complete. When you level up, you'll be able to access harder instances, get better gear and be able to handle more complicated encounters. This progression continues up to level 60.

At level 60, the levels cease to matter. Instances continue to progress through better itemization and more difficult encounters. First tries in Molten Core always seem to be quite complex if you are used to 5-mans or UBRS. When you master Molten Core, your guild has the gear required for Blackwing Lair, and knows how to arrange healing for multiple tanks. When you get better gear, you also learn how to handle more complicated encounters. This holds true all the way to Naxxramas.

Then let's add the expansion into the equation. Obviously the level progression starts again, and so does the gear progression. According to preliminary reports, simple quest rewards rival or exceed Molten Core and Blackwing Lair gear. This means that the vast majority of players will skip the current 20-man and 40-man instances altogether, because they can get better gear easier and faster in Outland. But what about tactics? How hard will the Burning Crusade endgame boss encounters be? Will the 5-man instances teach new raiders the skills they will need in endgame? I would feel pity for the guild master who tries to convince his guild to go back to Ahn'Qiraj to learn group coordination and caster tanking, for example.