...which are sounding exactly like server merges. They're just not saying that because, well, saying "World of Warcraft to Perform Server Merges" is a way of getting a LOT of negative press.
Patch 5.4 Feature Preview: Connected Realms
To be honest, it sounds more like what has been implemented for The Secret World and is being implemented for Age of Conan than anything else.
Still, they're server merges. No way around it. I've been perusing some online listings of active accounts on servers --I still wonder how they manage that-- and I've found that Ysera has dropped quite a bit over the past few years (down to something like 1/4 the size of Area 52), matching what I've noticed in game. I do wonder how this is going to work long term, and whether a Horde-heavy realm will be matched up with an Alliance-heavy realm to balance things out.
But the merges have begun. (Just don't call them that.)