The Paladin class is probably the only class that is really, notably more powerful in PF. That said, I still think it's 'meh'. It lost Turn Undead, which gave it access to a lot of the Cleric's neat tricks, which is a real downer given the increased focus on Charisma.
The rest of the caster classes are really not significantly better. They can juice their saves a little more, but that's not terribly important. Anyone worth anything uses non-save spells, anyway. Also, while the Fighter CLASS is better, all those bonus numbers the Fighter CLASS came out of Power Attack, which now sucks donkey balls, so, overall, a PF Fighter is still only breaking even with a Core 3.5e Fighter. Also, the Barbarian, Paladin, Ranger, and Monk all suffered stealth nerfs in this field, too, since they all also relied on Power Attack to deal notable damage, but didn't get the numbers backup that Fighters did.
That said, casters are really more-or-less the same. Some spells got nerfed, some got passed over, and their new class features really just about compensate for the spells that got nerfed and give them more interesting stuff to do than pick an extra feat every 5 levels.
Overall: Barbarian got nerfed, Bard got nerfed, Cleric is about the same, Druid is about the same, Fighter is about the same, Monk got nerfed, Paladin is about the same, Ranger got nerfed, Rogue got nerfed HARD, Sorcerer is about the same, and Wizard is about the same.