There was a moment in the Warlords of Draenor beta when I realized that I was getting a quest from Frank Welker. Aka Megatron. Aka Nibbler from Futurama. Aka a million other voices. The man has 728 credits as an actor on IMDB, and here he is, doing a voice in the Warlords beta. Specifically, Reshad the storekeeper. See, they recently added a ton of voice acting to the beta - pretty much every character you interact with has significant voice work put into it, and for the most part it's frankly stunning. I'm not trying to exaggerate here, but the difference between this expansion and, as an example, Lady Sindragosa's Betraaaaaaaaays you dialogue is night and day.
Heck, just pop over to Frostfire Ridge at level 90, or run through the Tanaan Jungle opening, and you'll hear a variety of voice actors, more so than World of Warcraft has ever boasted.
Warlords has taken the Mists of Pandaria approach with Lorewalker Cho and other important NPC's and it's rolled it out to almost every single NPC you'll interact with. I don't agree with the video's view on Star Wars The Old Republic but then again, I played TOR as a single player game. I do agree that the voice acting is much improved overall. It's kind of hard to differentiate some of the orc voices after a while, because you know, they're orcs and it all gets kind of growly, but for an example Farseer Drek'Thar is insanely well done, subtle, a voice that could absolutely belong to an orc but doesn't sound like any other orc.
Voice acting makes cut scenes and side moments much more immersive and alive. One of its best and most underestimated uses is in moments between questing, when NPC's talk to each other. It makes something that could be just another boring fetch quest seem significant, and it really helps you to get a sense of what the situation that's unfolding really means - having Khadgar and Cordana snark gently with each other helps move the story along and informs you of their relationship in a way that having a big box appear on your screen with a third party telling you about them can't.
I'm definitely recognizing a few voices - I swear I know Khadgar's voice actor, I already mentioned Frank Welker, and whoever's doing Drek'Thar is very familiar. For some people that might be a problem, but I like it - these are definitely actors who've done a lot of work in the industry. (It may not hurt that I recently watched I Know That Voice and saw Blizzard folks in it.) It's definitely a welcome change in terms of how they're going about their VO, and it takes the Mists approach and broadens it. It's a huge leap forward from, say, Cataclysm.