Typically a much more "crispy" crust, and (if you like this) cheese on the edges that gets "crunchy" (there's a term for this...have forgotten what they call it) - but crispy outside and softer inside.

Hard to explain really--but FWIW it's the only way we cook pizza now...

Oh--and super easy to clean up (assuming your cast iron is well seasoned). Literally just wipe out the skillet...