One of the reasons I wanted to start working on my Loremaster achievement was to spend more time out in the Old World before everything got turned upside down. When you are running around desperately seeking every quest possible, you also notice things you never bothered to before. And you pick up on some new things.
If you're Alliance, you may or may not have noticed a new arrival in Darnassus. His name is Archmage Mordent Evenshade of The Highborne. Actually, if you go near the city portals in Dalaran, there is a Highborne Nelf there offering a short quest that leads you to the Archmage (which counts for loremaster of Kalimdor! Wahoo!). Stick around and listen to the entire conversation the Archmage has with a Sentinel. It's not especially enlightening, but if you're wondering how on Azeroth Blizzard intends to justify Night Elf Mages, this appears to be the start of that lore revolution.
If you're Horde, head on over to Thunder Bluff, and stand in the giant tent over on Elder Ride, and listen to the discussion about Mu'Sha between Aponi Brightmane and Tahu Sagewind. A crisis of faith is on the horizon, potentially opening up new avenues of Light for the Tauren. Priests and Paladins incoming!
Blizzard has mentioned in the past that they don't want players to think they just threw in a bunch of new classes with no lore behind them, and I imagine these are some of their attempts to give a sense of foreshadowing for Cataclysm. The truth is, they are at the point now where story-line-wise, they HAVE to add some new lore is we want to see any new content. Okay, fair enough, I can accept that.
It's a great time to be working on Loremaster - new sources of lore popping up all over the place! I'm keeping my eyes and ears out for any other new NPCs.