Super-nodes!

Someone recently told me that, in a Chinese online forum dataset, a few very popular posts are commented by everyone and claimed that they may have up to hundreds of millions (!!) of distinct commenters! Generally, I’d find that hard to believe (number of commenters on a single post is at least an order of magnitude larger than the whole population of Greece, and about equal to the population of the US or Japan), but it may just be true in this case.