Final answer:
The musical from 2004 that featured puppets is 'Avenue Q'. It offered a satirical take on adult life using puppetry, following the trend of modern, satirical Broadway productions that gained popularity post-9/11.
Step-by-step explanation:
The 2004 musical that featured puppets is Avenue Q. Unlike RENT, which highlighted the lives of New York artists dealing with societal issues and was a revolutionary hit in the 1990s, Avenue Q incorporated a unique mix of both human actors and puppets to tell the story of adulthood and existential angst from a humorous perspective. Avenue Q proved to be a clever and contemporary satire, much in the vein of other notable works like Spamalot and The Book of Mormon, appealing once again to modern audiences with its fresh and unconventional approach to musical theatre post the events of 9/11.