U2 is still thinking about doing two distinct types of concerts when the band goes on tour in 2015. That idea first came up in the recent Q magazine cover story, and it was mentioned again when the band spoke with Rolling Stone magazine for its current cover feature.

RS has published some of the interview quotes that didn't make it into Brian Hiatt's print story, and those excerpts include this mention of how next year's tour might be structured:

The band is weighing a two-night structure for their 2015 tour.
"There is talk of doing two different kinds of shows," says Clayton. "One night would be a kind of loud, explosive rock & roll kind of event and then the other night's show take the acoustic arrangements of some of the songs, and kind of present those songs in a much more intimate way. But we don't really know how that's going to sound and look." One thing the band hasn't figured out: how to make sure audiences understand in advance which show they're getting.

In the article, Bono also seems to mention wanting to be able to converse with his younger self during the live show, since some of the songs are a conversation like that. There are also lots of album and song nuggets you probably didn't know about yet. It's a good read.