Pandora pays per play and effectively pays out 46.5% of revenues. Spotify pays out 70% of revenues and loses money. Apple is promising to pay ~71.5% of revenues. Just on that basis, Apple is paying more. (Spotify's 70% isn't worth much if it's not sustainable.)
Now, how Apple will pay for plays in the free trial period is probably by treating free trial users as though they are paying users for purposes of paying artists. I.e. they're paying for promotional tickets (which the labels do not do AFAIK -- that would be a marketing expense that comes out of your royalties). So they're still (probably?) not paying per play.
The point is, Apple was going to be 100% paid (aside from free trials), so that's a hugely better deal, and now the free trials are being paid out to musicians, which is the equivalent of a distributor eating marketing costs, something record labels, movie studios, and games companies never do.