World Champions? Surely you mean American champions. Didn't see any other country participating in the NFL this past year...
Of course, if the best players from each NFL team were picked to represent USA in a real World Championship and said "Team America" beat another country in the World Championship final - then they could claim to be champions of the world.
But it's not just American Football that claims it's winners are "World" Champs. Our local DiamondBacks were called "World Champions" when they won the World Series last year. Again, unless I missed it, didn't see any other country participating.
Anyhoo, nice to see the underdogs win. Nice to see U2 at half time. Cringed at the Mariah Carey lip-synch. Cringed at Terry Bradshaw and Paul McCartney butchering "A Hard Day's Night" - well at least one of them got the words right