The EU and U.S. communities were never really connected as well as they could have been. Because of ping differences, people from the U.S. generally didn't play on EU servers and people from the EU generally didn't play on U.S. servers. As a result, each community came up with different ways of playing / different rules for dueling. Europeans duel with only melee, Americans duel with melee, generic beams and kiblasts. It was only in 1.2 that the two began to play each other, at least a lot more than we did in previous versions.
@Manos: Your not fooling anyone, but ok.