Too Long; Didn't Read; Not Enough Pictures
Can also be pronounced tildernep (til-der-nep).
A quick reply to someone after they've sent you a link to a long boring web page which they said was "interesting" but all you saw as blah, blah, blah and not enough pictures.
As Americans, our attention span demands that everything be summarized to a quick sound-bite and be accompanied by pictures and/or video so that we may digest the data with very little effort. After all, we are busy texting, talking, watching TV, de-friending people, and reading several blog entries at the time we clicked your lousy link.
"My girlfriend forwarded me some link about global warming and it was totally tl;dr;nep. They should make a movie or something about it. Then maybe I'd care. If there were enough naked women in it. Score!"