From my side, I got in fine with no issues, but heard there were 17000 man queues for some realms. For the first hour it was served side latency of around 2-3500ms, reducing gradually throughout the hour. Overall it was as expected tbh, okay, but I played from Burning Crusade onwards, and much prefer it to vanilla and current WoW.
Preferred it when BC was THE expansion and you didnt have to keep track of 7/8 of them, all the lore, differences, achievements and additionally classes entwined in that.
No queues for my server and I'm loving it - played Runescape back in the day and a little Neverwinter recently but this is my first WoW experience. I can't explain how much time I've spent as a ghost, running back to my body only to die again!