The geometry of a pan can affect how easily moisture is driven off of food, and how rapidly a sauce will reduce. It's often claimed that the sloped sides of a skillet help moisture exuded by cooking meats evaporate more rapidly, allowing you to sear more efficiently. And this is true, but only given the same cooking area. In other words, a 12-inch skillet with a 10-inch cooking area will sear foods more efficiently than a 10-inch sauté pan. The corollary to this, of course, is that, given an equal amount of food that needs searing over super-high heat (some steaks, for example), the large surface area of a sauté pan does not offer any significant advantages over a skillet—you'll still have to cook in just as many batches.
