As reported by PCGamesN, WoW Classic hit 1.1 million concurrent viewers just yesterday.
TwitchTracker displays a peak concurrent viewership of 1.1 million viewers for August 26, and a peak of 19k channels streaming on August 26.
This same peak viewership was also reported by Rod Breslau via Twitter:
there are over 1 million viewers on Twitch for the launch of WoW Classic the hype is real for World of Warcraft #WoWClassic pic.twitter.com/kASqYL4GDf
— Rod Breslau (@Slasher) August 26, 2019
According Breslau, two channels primarily accounted for the majority of those 1.1 million views -- Asmongold and Sodapoppin with 280k and 111k views, respectively. It appears the latest sojourn into Azeroth is proving popular, indeed.