Lukas Mathis of Ignore the Code, set out on a experiment to study the relationship between comment length and comment quality. He made some interesting graphic charts that looks at typical commenting traditions like weird punctuation, CAPS LOCK, colloquialisms, and swearing. Swearing gave some surprising results:
What’s interesting about swear words is that not all of them are created alike. Some actually improve comment quality. Most notably, both «jackass» and «crap» seem to be reasonably good indicators for above-average comments.