How is this an illusion when you can trade/guild/raid with everyone in the connected realm? And why do you think it won't change anything? You don't think connected realms will impact AH, guild recruitment, finding pugs etc for low pop servers?
There is not as much urgency to do this to high pop servers yet. I hope Blizzard is using this time to test out the new tech and eventually connect every single server together to form a giant virtual realm.