Let me remind you that the whole discussion started by me highlighting the popularity of The Last Airbender (due to Netflix, as someone pointed out) by comparing it to a mainstream show. I could have taken any popular show but thought taking the one topping the charts would be enough to illustrate it. Apparently not, and in the future I must carefully review the viewing habits of the whole HN community in order to make a point and not offend anyone.
So let me revise the comment: The Last Airbender is as mainstream as any other popular show today.