I'm not saying the # of GitHub stars is a good reason to choose a framework.

But it is an indicator of it being something more than not-just-another-stupid-shiny framework that cannot be immediately dismissed.

I'd disagree--a lot of the JS folks I've met are like magpies and will star anything that looks remotely interesting on Github. It is exactly chasing shiny.

I normally treat stars as a bookmark, rather than as a declaration that I believe this is High Quality Work. Rather it's more along the lines of "I want to be able to find this easily at home when I have spare time next week".