Because there is music in the background, from time to time. Music about which some giant soulless conglomerate could claim WE HAZ COPYRITE!!!1!
Politics aside, this is why the Internet was invented, and why it is the greatest invention of all time: "The 30 Most Important Cats Of 2011."
Some of the commentary is pretty good, too.
30: The Saddest Kitten Of All Time
Kitten: "Sadness is not a temporary affliction to be shrugged off and discarded. It is a mode of being; a way of life; a heaviness on the soul that can never be lifted because its weight is the weight of existence itself."
You: "JESUS CHRIST LIGHTEN UP YOU ARE A KITTEN."
* (h/t: MK, via email, who suggests a healthy consumption rate: "12 days of Christmas = 30 most important cats.")