No sponsorships as far as I know but Bono and Edge are now on Fender's board of directors. He's pretty much free to use whatever. Also, we don't really know what his signal path is. They all use in-ears so it's possible that they aren't listening to the mic-ed amps at all but who knows. I assume Streets was done through the SDD and AC30.
I thought Bono had entered the stage all weather worn and face bashed in... but it was just Bruce. I thought he did a great job. He adapted the songs to his style and hearing his voice gives me the chills. Chris Martin... well he tried but good for him for achieving the dream of singing with U2 (I liked his 'Substitute' t-shirt).
PS I like that the Edge uses that cheap Fernandez strat with the sustainer in it. Oh, and there may have been a bit of Fender bias up there... 6 strats, 1 fernandez, 1 gretsch (Bono's giveaway), 1 Gibson I think. It's usually more balanced.