With the war against the scourge and the Lich King continuing in the expansion Wrath of the Lich King, you'd expect the Argent Dawn to play a big role once again. But that doesn't seem to be the case based on this blue poster's tone.
While we haven't discussed reputation factions for Wrath of the Lich King, I can explain that from a design philosophy we prefer to NOT give players more experienced players a distinct advantage when it comes to new content. If you take The Burning Crusade as an example, there was no reputation that gave you an edge in Outland or would speed you further. Based on this example I wouldn't think the current Argent Dawn faction would be re-used for Northrend. Source
Using the Argent Dawn for Wrath of the Lich King won't be a good idea since it will be unfair for new players who never bothered to build reputation for them and went straight to the TBC content. I'm very sure I know what they will do to fix this problem since Bliz did it with TBC already. They can make another faction that's tied to the Argent Dawn but completely separate. They did this same thing when they made the Cenarion Expedition, which is obviously tied to the Cenarion Circle but never shared he same reputations. Argent Dawn Expedition? Hmmm...
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