How does Blizzard explain the current Outland and Northrend experience after the revamped 1-60 experience?

That's broken I know, but still. Pandaren running about in that content seriously breaks the lore XD

I'm guessing it will get precisely the same explaination as I got when I killed Illidan on my Bligewater Goblin last week.

Precisely F.A.

There could be many routes of explanation. It could be there have always been the odd Padaren working in the factions, but because the models were never created, we never saw them in-game. They could have been fighting with us on the front lines as mercenaries, and we wouldn't know because the art assets were never put there or deemed important at the time.
Pandaren *were* considered as a race for BC. One of the ways discussed in putting them in at the time was that Pandaren *are* Azerothians, and with the oncoming demonic threat, a few odd Pandaren would go out into the world as mercenaries to help out against the oncoming threat. The problem with that was all of Pandaria was still closed off, and the Pandas would be sort of locked out after leaving, so there wouldn't be much to expand on in terms of lore, which is why they didn't really work at the time as *playable* characters, but could still be a possibility in lore for any of those time-frames.

They could be seen as during that time period, in short, as wandering mercenaries that, once they left their home continent, were unable to return due to the mists. And once the mists open up, they're free to go back home.

Panda dks?

I always think that it's more or less guard duty on the areas they've already been to. AKA when my character hits 60 they're asked to do a brief tour of duty out in Outland to make sure the Legion doesn't try anything fancy again. At 70, despite the LK being gone, there's still the Scourge to deal with, so we're basically on clean up duty.