Github stars mean very little. It is free to give one and many people just star every repo they see.

The #1 repo by stars is FreeCodeCamp. I have not used the service, but if https://news.ycombinator.com/item?id=11911647 is to be trusted then the count is inflated:

> GitHub part is so flawed... because FreeCodeCamp inflate their popularity by requiring during onboarding for the user to star their repository yet keeping them at the top. It's like if I told everyone to vote up my Hacker News posts... and gave them the link to do it and GitHub has no remedy for that inflation.

I'm also guilty of starring repos that seem cool but have not read the code or tried to use it. I've never used D3 in a project and can't speak to its quality, but I've seen some wicked cool demos and starred it as a bookmark of sorts.