There was an in-game voice thing in Wrath. Thought it still existed.
Also, speaking of Mists of Pandaria, I found this tidbit funny:
Vaneras wrote:
We are absolutely thrilled about adding a race that can be played by both factions, but we are of course aware of the paradox behind pandaren of one faction not being able to communicate with pandaren of the opposite faction. This is a particular situation where we feel that the story must yield to gameplay, because it is our opinion that limited cross-faction communication is a vital part of the World of Warcraft experience, which we feel is not something that should change with the introduction of a neutral or cross-cross faction race.
http://eu.battle.net/wow/en/forum/topic/2868760485?page=2#24
Silly language barrier. It's not like people haven't bypassed it since they brought it up anyway. And it only got worse when they allowed cross-faction character creation on PvP servers.
And like someone else wrote in that thread:
Quote:
So, I guess the Pandarens won't be all "Hey, what's uuup!" when they meet each other in combat after all then.
There are a couple of theories up on the EU boards as to why Pandaren can't communicate with each other in MoP. Some suggest that it's a Matrix style blue/red pill thing while others are leaning more to the Pandaren being brainwashed by the Naaru.
Lore, lol comes to mind.