TM takes hints from a lot of sources - including HN. It has 30k+ sources that it directly crawls itself as well, and uses a lot of different hints to work out w

TM takes hints from a lot of sources - including HN. It has 30k+ sources that it directly crawls itself as well, and uses a lot of different hints to work out what is popular. The biggest hint to a big story is inbound links from other blogs that are also sources, and from there things like popularity on social media