I listened to it, too. Can't even tell you why, since I don't watch "Glee" (or any regular series TV, for that matter).
But I assume you all mean "head voice," because there's no falsetto here. He's a tenor going into his high belt range for the last part of the song, and that's called "head voice."
"Falsetto" is Frankie Valli and Mickey Mouse and the Beach Boys. And countertenors.
"Head voice" is a mix between "chest voice" and "falsetto."
*end of voice lesson*
"Jaws is the Citizen Kane of movies."
blocked: logan2, Diamonds3, Hamilton22