Depending on who you ask, The Simpsons has been on a downward slide since season seven or since season ten. One fact that can't be debated is that the general quality of The Simpsons keeps on declining. There isn't a fan alive claiming the newer seasons trump the classic ones. However, even in its ailing years, the Treehouse of Horror is still a bright spot that fans of Springfield's favorite family look forward to every year. In the eyes of some fans, The Simpsons' annual Halloween special has transcended the series and almost exists as an independent piece of pop culture.
In recent years, the Treehouse of Horror has become famous for hiring special directors and animators to give the annual special a little extra buzz. Even though the year Guillermo del Toro directed the intro was pretty awesome, this year's guest spot might be the best one. In the video linked above, you can watch The Simpsons pay homage to Death Note in a short animated by the same talent behind the legendary anime.