At any rate, the SoundCloud blurb says,
"Sound construction piece featuring Lips, Erykah Badu, Siri, and Biz Markie backwards. It's called 'Now I Understand' It's funny and will be available on SoundCloud for one week only!!! Life is beautiful. Music gets you high."
Siri apparently then "gets it," as the iPhone 4S replies, "Wayne, now I understand." Listen to it, and see if you "understand." And see if you hear Biz Markie backwards, too.