I played a lot of 4e, and only gave it up fairly recently. We found fights went very, very slowly, but I suspect that's going to vary by group. for example, my group hated the fact there were 3 or 4 different bonuses being generated every round in 4e. When the cleric sets up a foe so the first person to hit him gets healing, the ranger grants bonus damage to anyone next to him, the fighter gives bonus AC to anyone next to her and the warlord causes one foe to grant combat advantage to the theif (but no one else), and some beholder is creating a set of difficult terrain, or slowing the cleric, or whatever, and that whole list changes every round, we got bogged down.
At first, we thought we just weren't used to how the new system worked. But after more than a year of play, it didn't get any better. In fact, the constant influx of new powers, with new conditions, made it worse. And the online character generator was so useful, no DM wanted to forbid characters made with it, so we always ended up allowing in all WotC content.
For us, it is much, much easier to deal with a bless spell, a bardic performance, and a bull's strength for the fighter. We note those down, keep track of durations, and don't have new statuses popped up several times a round. Fights take us half as long, and even less when someone does something clever and bypasses a foe (which never seemed to happen in 4e, because the numbers always made sure every encounter was a balanced challenge, no matter what the players did).
But again, I suspect another group might find per-round bonuses faster than we did, and maybe even the broader changes Pathfinder spells can bring to be slower.
That's been my experience as well. Pathfinder combat has been so much faster than 4E combat, and not having to deal with the fiddly round to round conditions/buffs/debuffs really helps improve the flow of the game.