The best tool for tracking specific interests.
Lots of updates, UX changes have been pretty dramatic.
I used it to keep track of company acquisitions as well as topics like game cheats, mushroom farming and product recalls. Then I expanded my interest lists include things like "charcuterie" and "michelin star restaurants in sf". Everything works really well.
The team has a crawler or indexer that doing realtime search and seems to be tracking social media as well. My interests are persistent and I can follow anything. I think was one of the top products Twitter was musing about building in 2017, but didn't.