Gennari is a well-recognized and highly respected scholar in a number of fields, including English, American Studies, African-American Studies, and jazz criticism. He is the author of Blowin' Hot and Cool: Jazz and Its Critics (University of Chicago Press, 2006), winner of the 2007 John G. Cawelti Award for the Best Book in American Cultural Studies, and of a 2007 ASCAP-Deems Taylor Award for excellence in popular music criticism. He has authored many articles on jazz, Italian American cultural studies, visual culture, and sports. His courses at UVM include "Jazz and the Cultural Imagination" and "Caruso and Cannoli, Sinatra and Sopressata: Music and Food in Italian American Culture." Gennari has received fellowships from the National Endowment for the Humanities, the W.E.B. Du Bois Institute at Harvard University, and the Carter G. Woodson Institute at the University of Virginia. He is currently working on two book projects: "The Jazz Salon: Lenox, Music Inn, and 1950s America," and "Passing for Italian: Crooners, Gangsters, Celebrity Chefs and Other Italian Poses in American Culture."

In the UVM community, he's recognized as a leader and activist, and a "devoted and engaging teacher who brings excitement and creativity into the classroom," and one who also "opens his home and office doors to students who 'just want to chat' about whatever it is that has piqued their interest." His students often describe him as "challenging" and "passionate," and say that his classes are some of the best they've taken at UVM. John's dedication to students also extends beyond the classroom, evidenced in his "tireless role as advisor" in the English Department and Director of ALANA U.S. Ethnic Studies.

Professor Gennari's Dean's Lecture on April 2, 2008 was memorable. Entitled "The Sounds and the Fury: The Acoustics of Afro-Italian Life in Kym Ragusa's The Skin Between Us: A Memoir of Race, Beauty, and Belonging," the lecture was a tribute to the sounds of Afro-Italian life. Describing the lecture he was about to give, Professor Gennari wrote: " 'Race' thinks primarily with its eyes — and has done so through visual discourses of science, spectacle, and surveillance ever since the Enlightenment. But what happens when we open both our eyes and our ears to the nuances of interracial perception and interaction?" "We must learn to judge a society by its noise," exhorts cultural theorist Jacques Attali, lamenting the decline of listening in modern Western culture. Gennari goes on to say: "When we tune in to the noise of African American and Italian American life—from joyous barbershop and bandstand buzz to intense silence borne of suspicion and fear—our ears ring very loudly indeed."

The College of Arts and Sciences established the Dean's Lecture Award series 17 years ago as a way to honor faculty members who are both excellent teachers and highly respected professionals in their own disciplines.