If you missed the announcement, in the upcoming Patch 5.4, this feature is being tested on the PTR:
Patch 5.4 adds Virtual Realms, which will essentially merge lower population realms. This will allow you to keep playing on your current realm, but do arenas, raids, and dungeons with people in your realm group, as well as use a merged Auction House and trade with other players in your realm group.
Yes, merged Auction Houses are coming your way. What does this mean for you? If you’re currently making gold via arbitrage (selling into scarcity), your life is about to get much, much harder. Ask any Guild Wars 2 player how much fun using the Trading Post is for arbitrage. If you’ve not played, the short answer is that everything is a commodity and nearly all common materials are sold at or even below cost.
Depending on the sizes of the merged Auction House, WoW players may soon find that the bulk of the market will become commodity markets instead. Make your gold now, before 5.4 rolls out!
Published: Jun 12, 2013 11:48 am