As far as the spoilers thing goes, I'm not really sure how I feel about it. Luckily or otherwise, my hand is forced on the matter, because of my role on U2gigs.
Sometimes I think it'd be nice to be surprised. On the rare occasion when something has happened that has been missed by all the spoiler whores (like when U2 did a secretive soundcheck in Coimbra and played Boy Falls From The Sky), it's quite fun. Though it is U2, meticulous and pre-planned to the nth degree, so any surprise or spontaneity is basically fabricated. I know there's an element of kidding myself whenever there's a moment of "oh my god I can't believe they're doing that!", because of course I can, it's U2 and they thought about it too fucking much before doing it. For the record, if I am actually at a gig and given the chance to look at the setlist prior to the show, I turn the chance down (though I make sure somebody else knows it, in case the band deviate - I would probably look if I didn't know any reliable person who wanted to peek).
There's also the point that sometimes rehearsals and soundchecks are the only way to hear some songs. This tour, so far the only way you could have heard Drowning Man, Even Better Than The Real Thing, Tryin' To Throw Your Arms Around The World, acoustic Mysterious Ways, and full band North Star was via spoilers. A number of infrequently performed songs have been heard by more fans thanks to soundchecks and rehearsals than at actual concerts.
And the way U2 fans blab, it's hard to avoid spoilers even if you try. The folks I know who tried to avoid spoilers prior to the first leg last year generally had the biggest surprises (like UF) spoiled well in advance.