Pet peeve

[kane_magus]

"tl;dr" is the Internet equivalent of saying "I am lazy and stupid".

Comments

[kitten-faust.livejournal.com]

> "tl;dr" is another sign of an unsuccessful Internet troll

Actually, I haven't seen anyone seriously use that in a very long time; it's usually "(long post) tl;dr: (maybe witty summary)".

[kane-magus.livejournal.com]

I still see it fairly often, enough so that I'm long past sick of it.

I've used it myself on occasion in the sense that you're talking about (i.e. writing a long post, then putting a short summary at the end prefaced by "tl;dr version" or some such), but yeah I still see plenty of morons using it in the original manner (i.e. someone writes something with more than two or three paragraphs in it, and then someone else comes along and posts an annoying, single line "tl;dr" comment in response).