This all sounds so simple and outrageous, doesn't it: "The British Journal of Photography reports that the band management for Coldplay has been asking concert photographers to sign a contract giving the band all the rights to their photographs" (found here).
(Updated below)
But let's look at the bigger picture (bad pun, unintended): Most musicians make very little money from sales of their albums. Instead, they rely on concerts (and other stuff) for their income. Seen in that light, it makes perfect sense for Coldplay (or any other musician) to claim the copyright of images taken during their shows.
In a nutshell, we here have a situation where one group of artists is pitted against another one - while plenty of other people (for example Ticketmaster or record labels) make money off of both of them.
It seems to me the solution to this problem is not to see which artist gets which fraction of what they're currently fighting over but, instead, to see how those other people (Ticketmaster or record labels) get less money, while the artists get more.
Update (19 March 2009): "Prince is seeing into the future - again. In 2004, he gave away a copy of his 'Musicology' CD to everyone who attended one of his concerts, making concrete what is now almost axiomatic: recordings have become advertisements for shows." (story)
