I have a strange relationship with GitHub stars. On one hand, I love them - they give my projects exposure (I always mention cleaver [0] during my interviews) and let me know how many people are "using" my project.
On the other hand, I feel it sort of pushes me in the wrong direction. Stars aren't a good indicator of use, or even importance. For instance, cleaver is not technically challenging, yet it shares the same number of stars as numpy [1].
So, not sure how I feel about them - not sure what they measure.