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…
Snapchat has always positioned itself as a temporal messaging app, where anything goes - but only for a few seconds. It's always meant to be the foil to our Facebook, Google+, et. al., culture of heavy-hitting, abundant, follow-you-everywhere data trails. Why they would embrace this functionality - betraying their core value-proposition - is puzzling.
Whether this data has been theoretically accessible for some time now is somewhat immaterial - unless we're collectively proving our cleverness by correcting the author. The take-away is that Snapchat has seemingly flipped it's core promise - a non-permanent trail and ostensible privacy - by including this "top friends" feature.