There are two major differences that affect performance of forged- versus cast-iron pans: method of manufacture, and material. Forged pans are stronger than cast-iron ones, allowing for thinner walls that heat and cool faster, subal says. Second, forged iron is made with much less carbon than cast iron, which makes it less brittle (that explains the thin walls, GH1618 says). In fact, forged-iron pans perform a lot like carbon steel ones. Naturally, a pan with thin walls is easier to pick up and maneuver.
Apart from that, if you keep both kinds of pans in good condition they perform pretty much the same, Rigmaster says. That is, unless you acquire an authentically hand-forged, hand-hammered forged-iron wok, which does perform better than a machine-made one. All those small indentations or imperfections from hammering by hand allow the wok's contents to stick to the sides better.
Discuss: Forged iron pans?
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