Judges Simon Cowell, Britney Spears, Demi Lovato, and LA Reid made their debut as a foursome on a Wednesday night (September 12) broadcast which garnered 8.5 million viewers.
According to Mashable, the episode got a total of 1.4 million comments from viewers on both Facebook and Twitter, setting the record for the most talked about series premiere of all time.
Viewers apparently talked the most about contestant Jillian Jensen's rendition of Jessie J's ballad 'Who You Are', which caused notoriously blunt judge Cowell to become emotional.
Her audition is said to have generated 17,067 comments per minute.
Despite its popularity online, The X Factor still lost ratings-wise to the third and final instalment of The Voice's third season premiere, which netted 12.3 million viewers.
Watch Jillian Jensen's X Factor USA audition below: