[S]ome important things about the "poetics" of rap are lost in a purely textual presentation of the lyrics. One student observed that in pieces he knows, the rhythm is there in the written form — but the lyrics for pieces that he doesn't know seem flat and lifeless in comparison.
There are good reasons that this is more true for the works of Melle Mel or Jay Z than for Elizabeth Barrett Browning or W.H. Auden[.]From Language Log.
As the post explains with scientific precision and illustrations, one of the key points that is missing is that rap is presented against underlying beat and that placement of words at different points relative to the rhythmic background affects the feel and makes the combined rhythmic structure far more complex than it seems on a printed page.
For example, while the music alone might be in 4/4 time, the timing of the words in a rap may make 16th note length time periods fundamental with off beat and on beat words having a different impact. The rhythmic structure often changes a great deal between stanzas and choruses as well, breaking up monotony.
Mark Lieberman's post suggests that older poetry doesn't do that. In the case of Browning (flourished early to mid-19th century) or Auden (flourished early 20th century), he's probably right. But, in the case of classical Greek lyric works right on the brink of the transition from oral tradition to written accounts, and even in Shakespeare, I'm more skeptical. A great deal of nuance may have been lost in the transition to the written word in those cases.
"It's a thing."
I've heard the phrase "it's a thing" out of my daughter a lot in the last year or so, meaning that something either has a secondary meaning (in the trademark law sense) or that something is part of a (newly established) shared cultural practice. The phrase even has its own twitter feed. A blog at the Chronicle of Higher Education noticed the reinvigoration of the phrase eight months ago (the frequency with which it is used, rather than the usage itself is what is really mostly new, the idiom passes the mutual intelligibility test back to decades before I was born), but being around college students all the time keeps you at the cutting edge of trends like this if you pay attention, so I don't fault myself for being oblivious.
For example, "Why are you wearing no socks, but a long thin shawl to school?", I ask. "It's a thing.", I'm told. The phrase can apply to text messaging conventions, instagram, decisions to participate or not in certain activities, or pretty much anything else that an anthropologist would call a "folkway."