It may have changed recently, but during the past year or two, you actually couldn't find an American made 92FS in the US, as the US plant was strictly running M9's. They were bringing all the commercial 92 FS's in from Italy. I have both, and there are no real differences between the American and Italian 92 FS. The only one I know of for sure is the hammer cap pin on the Italian guns is a roll pin that must be drifted out with a punch, not a straight pin like the US versions.
The standard M9 has a straight dust cover and non-radiused backstrap, along with the gov't markings. The 92 FS has the slanted dust cover and the radiused backstrap. The M9A1 (or 92FS type M9A1 as it is officially labeled), has the accessory rail, front and rear checkering on the grip, and a beveled mag well (just like the Elites). Otherwise the controls and features are the same between all 3 variants (92 FS, M9, M9A1).
They are all on the Production list these days, too. Until I found my E2 over the winter, I was using the M9A1 as my primary gun.