The Blade’s Edge and Thunderhorn realms will join Agamaggan, Archimonde, Burning Legion, Jaedenar, Kargath, Norgannon, and The Underbog.
Almost TEN SERVERS LOL
Listen I’m from Archimonde alliance and our server was dead and gone we were like 90% horde and I’m glad to have alot more friends to kick it with but does anyone else think that’s wild to have nine servers!?
Unless I’m wrong, it’s very likely that all of those servers are very scarcely populated (I’ve never seen a player from any of them except 1 from Agamaggan and I think 2 or 3 from Kargath). Enough to make it worthwhile to merge them without overloading the home server. Sadly, this means farming or camping certain mobs will be more difficult but at least you won’t be sad and lonely anymore.
I used to play on Thunderhorn, the place was a ghost town at times. Literally empty trade chat for over an hour.
Can’t speak for the other servers but it sounds like a good merge.
/waves
Now you’ve seen a player who is originally from Thunderhorn. My first main is still on that server actually. Troll warrior. 
Thunderhorn/Blade’s Edge have been in a rough spot for years now. Good to see they’re getting some attention. Hopefully with so many servers combined there will actually be a bit of a population.
Even at WoW’s peak like a decade+ ago, there were servers that were just outright dead.
Right now, you could merge the bottom like 80-90 realms into like maybe 10 decent sized ones.
Multiboxers can create 50 toons on the connected realm and try to play AH baron.
Seriously, I was on Blade’s Edge back in WoD and it was dying then. I cannot imagine where it’s at now. It was so bad that we couldn’t find a magic caster for HM for like a 13m roster.