Github is a reliable source but I am not sure whether it is representative. At least it appears to be very popular with web folk. Other sources are missing such as bitbucket, especially since it allows for free of charge private repositories. Like this, the only thing this says is that github use correlates with the lines of JavaScript. Not sure whether this is a good measure for popularity. Much like a kid in kindergarten, who shows up every day and talks to everyone. Yes, his presence correlates with the presence of others, but what if he is just a jerk and nobody really likes him?