At face value, it is a little weird seeing those types of units running around Scarlet camps, but the answer to their change in ideology is actually very simple.
The Scarlet Crusade has been run by demons for several years now. First Balnazzar and then Mal'Ganis. From what I can gather from quests and lore, the Scarlets are the worst kind of brainwashed, and while their zeal may not be fabricated, their leaders certainly are.
Why is it that demons (like Archimonde, Kil'Jaeden) cannot enter Azeroth by just traveling here, but have to be summoned into this world? It seemed true with Draenor as well, that they needed to have portals opened to send in armies.
If Kil'Jaeden can throw an iceberg containing the Lich King into our world, why can he himself not enter? Why hasn't the burning legion just showed up and wiped us all out if they are so hell-bent on doing so?
The basis of the portal argument seems to be that the bigger and more powerful the demon, the more difficult it is to send through a portal. That's why it was a fairly easy matter for the Legion to send troops to Draenor but significantly more difficult to send Kil'Jaeden to Azeroth proper. Each portal is essentially opening a door from one dimension/planet to another, so it seems reasonable to consider that more energy and skill would be required to open much bigger doors.
Alex's Addendum: We can also probably assume that the Legion doesn't really have other ways of traveling here besides portals. The only other means of transportation that we know about is the Naaru's interdimensional ships, and the group of them that the Exodar is a part of are the only ones we know about. Kael'Thas had them briefly, and probably was more than ready to hand them over to the Legion, but that didn't pan out. They're back in the Naaru's proverbial hands. Until the Legion gets their hands on those, I don't think they have a choice in how they reach other worlds. What is Kil'jaeden going to do, ride a bicycle across the multiverse?
Wasn't there supposed to be some extra goodies for those who took the leader role in a random dungeon (or am I just imagining that I read that)?
The quote at the time was something along the lines of "you'll get extra bonuses for leading a random group." I guess what they actually meant was participating in a random group -- the rewards are the extra badges and money you see when you do random DF heroics/instances now.
I've just noticed that after the patch there are new guards, Kor'Kronn Overseer in UC. What did I miss?
Post-Wrathgate, Sylvanas is in the doghouse with Horde leadership, and the Kor'Kron Overseers are the new guards in the Undercity. Where are the abominations? Well, Thrall put a moratorium on making any new undead creatures, according to conversations between the Apothecaries and the Overseers, and any remaining ones were destroyed. The Royal Apothecary Society has been nearly dismantled, and what work is still going on is being very closely watched by Thrall's best.
Is it working as intended when you heal yourself when casting a spell with no target selected? I find myself burning Surge of Light on accident all the time now, I miss hitting Alt + healing spell to heal myself. I'm not a fan of this change at all.
You very likely turned on the Auto-Self Cast option in your stock UI by accident.
Are there any new of those short breadcrumb quests introducing the new race-class combinations in 3.3? We've seen night elf mage and tauren priest and paladin in recent patches.
Not in this patch, but Kisirani promised we'll see a ton of lead up to these new combos, including progression of the quests you've already seen, so I guess we just have to wait. I want to see the bits about gnome priests and troll druids, that's for sure.
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