Well, there's definitely a variety of meanings - without naming names, I recently read an exchange on LW where 'tl;dr' was explicitly used as a synonym for 'summary', divorced from either interpretation of the acronym ("I plan on reading that link later, but for now do you have a tl;dr?").

Edit in response to your edit: Yes, well... I don't have to stop and think about its meaning, is the thing.

But I get your point.