Looking at the top ten just now, five of them are programming-related. (The others are social networking, UI, computer games, physics, and the London fatberg)

Looking at the top ten just now, five of them are programming-related. (The others are social networking, UI, computer games, physics, and the London fatberg) Of the next ten, another five are also programming-related. (The others are either business-related, about automation, or this post.) So it looks rather like 50% of HN is programming-related. (From a tiny sample-size, admittedly.)