His album Victory For The Comic Muse was the surprise choice in the Irish equivalent of the Mercury Music Prize.
The 12 judges - including Hot Press's own Stuart Clark - agreed on Divine Comedy, despite Duke Special being the odds-on favourite to win and Snow Patrol being the most commercially successful.
Hannon joins last year's winner Julie Feeney as being the recipient of the prize, which is e10,000 provided by the Irish Music Rights Organisation (IMRO) and the Irish Recorded Music Association (IRMA) - as well as a specially-commissioned award, courtesy of the Recorded Artists And Performers Ltd (RAAP).
The event saw eight of the 10 acts perform at Vicar St, with the co-organiser of the Choice Music Prize Jim Carroll paying tribute to the venue's former owner, Jim Aiken, who died on Tuesday.