Personally, I think radio edits are, on the whole, not nearly as good as the original songs. A song is however long it is, and that should be the end of it.
The problem is, as someone else pointed out, that radio stations generally won't play 'long' songs. And that is just symptomatic of society today, where people want instant gratification and if they don't get it, they're not happy.
It's a very sad state of affairs. A brilliant example is table-tennis. Recently, they changed the rules in the game, reducing the number of points needed to win a game from 21 to 11 (think they're the right numbers). They also made the balls smaller so that the game was faster. The reason? Because people weren't prepared to sit and watch a whole game of table-tennis anymore. Ergo, they've made it shorter - they've done a radio edit of table-tennis. Same reason the one day test was introduced into cricket.
Sadly, through no fault of the musicians, the masses aren't on the whole prepared to listen to lengthy songs. And at the end of the day, U2/their management/the record label are ultimately out to sell records, so they're not going to release something that won't sell so well.
The thing we have to ask really is whether it actually matters to us fans? I've heard the edit (thanks to a kind poster on this thread
)and it's not nearly as good as the original, because that's not how it's meant to sound. But, we've all got the record, so we can hear the song in its entirety, as it was meant to be, anytime we want. Ultimately, I don't think it's that big a deal, other than, as I said, the way society is tending.
But isn't the cover gorgeous?