The most obvious difference is the reinforcement of the derailleur-hanger stop-tab. The Taiwan dropout uses a "sharkfin", whereas the campy dropout uses a nautilus shape that follows almost the entire radius of the derailleur hanger.
http://www.seashells.vg/
To my way of thinking, the italian campy dropout seems to have a larger and much more aesthetically-pleasing cutout window than the taiwan campy dropout.
- Don Gillies
San Diego, CA, USA