I would like to briefly provide a little bit of information about what I roll and what you roll. Keep in mind that these rules aren't hard and fast, and I try to give players the benefit of the doubt in all cases.
I typically will roll what might be called "passive" perception checks for all characters upon entering a room or scene, and for what in some previous editions would be called Spot or Listen checks. When you walk into a cave, everyone automatically gets a Perception check to be attentive to what might be in the room (to notice a goblin hiding behind a rock whose foot is sticking out, or to hear the sounds of wailing from deeper in the caves).
What I usually do not roll for is what would have been called in previous editions a Search check. You walk into a room, and with the "passive" Perception I tell you the detailed description of the room, including the fact that you find a chest. It is up to you now to say that you carefully examine the chest for traps.
Another thing I almost always will roll for would be things like Knowledge checks, Heal checks, Craft checks, and so forth, specifically when they are used to know things. You find a corpse; I'm not going to ask you to make a Heal check to determine cause of death, I'm just going to roll it for you. These sort of things seem to speed up the rate of play. I don't want to take away the thrill of rolling from players, but there is still plenty of opportunity for that.
Initiative is the other big one. I see no reason to wait around for six people to get around to rolling for it, when I can just get it done all at once.
