Welcome, tourist! Now you have more chances to group up, compete and connect with other players.
It's no great secret that World of Warcraft - though it still has a hefty player base and is the premier subscription MMO - is losing subscribers. Plus, players being the flighty little weasels that they are, folks tend to migrate from one realm to another in their search for a perfect home, but that can lead to some realms being virtual ghost towns while others are a little overpopulated. This doesn't just have an effect on the immediate will-someone-group-with-my-rouge-no-wait-rogue experience; the knock-on cripples the auction house, and has a significant effect on realm economy. Thus Blizzard is introducing Connected Realms in patch 5.4, a system in which two or more standard realms are seamlessly linked. Welcome, tourist from underdeveloped realm A! Say hello to the shiny consumer goods found in realm B, and by the way, would you like to group with a rouge?
"These linked realms will behave as if they were one cohesive realm," says Blizzard, "meaning you'll be able to join the same guilds, access a single Auction House, run the same Raids and Dungeons, and join other adventurers to complete quests." Blizzard doesn't want this to be any more disruptive than it absolutely has to be, and merging realms has its own complications. Suppose someone went on hiatus, and wants to come back because the latest expansion - Kingdom of the Penguin Goddess, say - is out. If that player's realm got merged, there's no home to return to. Or suppose two or more players in the merged realms share the same character name; how does that work? Thus Connected seems the better bet, from Blizzard's point of view. Players, it's hoped, won't notice a thing. They won't even see a home realm indicator, except in chat; as far as the users are concerned, everyone's in the same Azeroth.
As to exactly when this will happen, Blizzard hasn't said. Sometime after patch 5.4, is the ETA. "We want the experience to be seamless," says Blizzard, "and we expect it work as if you're suddenly part of a much more active realm." So if you should notice a bunch of tourists hanging around the local inn, now you know why.