Most of the comments are focused on the author's trivial mistake (when was this information surfaced: now, or at launch?). His substantive point is more valuable to bring to light.
Perhaps the fact that there are top-users lists highlights the tension between what Snapchat says that people use it for (sharing brief moments with friends) vs what people actually use it for.
In fact, I actually use Snapchat for sharing photos with friends, and I still would prefer that this network information disappear. The existence of a top list suggests that there is quite a bit of metadata retained long after the photos are (ostensibly) destroyed.
It implies that the company is building a database that could be used to reconstruct an enormous network diagram.