It's hard to say what songs they will drop because their setlist in Elevation was quite varied. It might be easier to predict wht songs they'll play in their setlist.
Their setlist should be:
NEW ALBUM: 7 new songs
SONGS THAT ARE HITS THAT THEY JUST NEVER DROP: 4 songs -Streets, One, Pride, WOWY
SONGS THEY WILL RESURRECT FROM THE PAST: probably 1 song (dont' know yet what, but didn't Edge promise they have rediscovered some songs)
B-STAGE SONGS: 2 songs (candidates are Desire, Stay, All I Want Is You, Angel Of Harlem, Staring At The Sun)
SONG EDGE SAID THEY'LL PLAY THIS TOUR: Electrical Storm
COVER SONG: 1 song (although they didn't have one during Elevation until towards the end of the tour, they normally do have in the past, from Knockin' On Heaven's Door to People Get Ready to All Along The Watchtower to Satellite Of Love to Edge's Karaoke bit)
TWO SONGS FROM ATYCLB: Beautiful Day, Walk On, or Elevation
So that leaves us 3 more songs, and if I'm wrong in some of the above the others should mostly be right ...so lets say at most 6 songs. So the question is ...which 3-6 songs are they going to play?
3-6 songs isn't much to choose from so I think they will choose their songs that have been released as singles and have gotten popular throughout the years.
I think they will probably finally drop Bullet The Blue Sky and Until The End Of The World.
So possible candidates for this 3-6 songs include I Still Haven't Found, Sunday Bloody Sunday, I Will Follow, New Year's Day, Even Better Than The Real Thing, Mysterious Ways, Bad, Gone, Discotheque.
The problem with U2 is that they are too popular for their own good. They keep churning out hits 25 years into their careers. No band is supposed to do that. Now U2 has a dilemna, they surely cannot put up a show that will satisfy all the fans since many favorites will surely be excluded. It's their fault for being so goddamn good. The only solution to this dilemna would be to get rid of the front act altogether and just play three-hour shows!
Cheers,
J