source gaffa.dk : this includes a trailer for the movie about Nelson Mandela:

http://gaffa.dk/nyhed/77429

^ the new song by U2 is at the end of the video clip,

(article is written in danish sorry)...

[Edited 10/22/13 9:21am]

you can hear the new song by U2 in the last 1 minutes and 15 seconds of the movie trailer.

(But it includes dialogue from the movie)

Sounds like your basic slow earnest U2 song that builds

to big climax with a choir as background singers.