The massive upvoting of the snarky "oh, snap" comments that followed, is what was surprising.
You are supposed to upvote intelligent discourse, and downvote the cruft; ie. encourage the "community and the discussion that goes on here", and discourage the "anonymous trolls that don't think before they comment". Or at least that's how I learned it.
The reverse seems to have happened.
See: "indeed" +12
"memo to self: stop using ticketstumbler.com" +34
"Such a shame, but I won't be using it either." +9
"TicketStumbler founders - Get a life." +4
"You think the people on here are dumb enough to believe that what you posted was an "experiment"? You're an asshole." +21
"Just apologize for the comment, man. You're not going to change anyone's mind with a childish rant like this." +20
"Posting comments irrelevant to your initial insensitivity will not help save face, especially when you throw in an attack towards the entire crowd." +18
or the especially ironic "I actually had to scroll up to the banner to make sure I was still on Hacker News and not reddit." +12
As far as I can tell, those are on the same plane as the original comment.
It was the upvoting of these (and similar) inane, and snarky one-liners that I was surprised at, not the downvoting of the comment that set it all off. Although the upvoting of the "golly gee-whiz, that's awful bad, hyuk" type comments, and the intertia of the downvoting of the subsequent comments were also surprising.
It appears as if the score of some of the other comments, ie. "You're an idiot" seem to be stabilizing over time. It's no longer +5, at least.