This law is unfortunately too little known. Here is a nice and short primer. Be careful though, it's short but packed with information, might require more reading around the concepts highlighted in this article.

Definitely a big announcement for Matrix. Could it be the beginning of going mainstream? I suspect it'll be now or never. I'm slightly concerned about the desktop support being apparently ignored, the UX there is far from great still.

When I read the content of this article I wonder how useful the metrics really were. I mean clearly they helped the team realize which changes to bring... but the practice changes were all somewhat conventional in a way. You go a long way when you focus on quality and create the space for it.