[patorjk]

I'm having trouble understanding the follower visualizations. Does the X axis represent her followers in the order they started following her and the Y axis is the date they (the follower) joined Twitter?

[7dare]

The original article suffered from the same flaw, and they never really explained it.

[duskwuff]

Correct.

It's a kind of weird visualization, but the patterns which emerge are pretty striking (and obviously artificial).