https://www.reddit.com/r/classicwow/...uding_pvp_pve/
In China, by a Blizzard executive producer. But since the players in China are no less than those in NA, probably there will be no more than 8 severs in NA. For EU, the situation would be a bit different.
This means even in phase 2 when the layers are no long exist, there should be more players in one server than the numbers in 2005. I am personally glad to see a peak 10000 online in one server, which is similar to private server. Edit: The number 10k is just my guess based on that they said there will be no layer in phase 2 and the assumption they don't add many servers and don't enable transfer before phase 2.