Pandora is redesigning itself in a way that goes well with iOS 7. Their new icon is flatter and simpler. Pandora said that the new changes will soon be available on desktop and Android devices. Pandora 5.0 doesn’t change any of the working parts (that I can tell) but rather just the design aspects. In other words, you’ll still use Pandora that same way you used to.
It also appears as though Pandora is switching over to a new font. Besides the icon and splash screens, Pandora has also changed the way their UI looks.
With iTunes Radio about to make its debut, Pandora’s future is unclear.