우와. 완벽합니다. 놀랍군요. -.-;;; 혹시나 이의 있으신분 있을까 싶어, 카탄 제작사 홈피의 Q&A를 퍼왔습니다.
내용은 위의 글과 동일하군요. ^^

============================================================

Q: If Player A has a road that is 5 pieces long, and player B then builds a road that's 5 long, who gets the Longest Road bonus? To interpret the rules literally, it would seem that player A keeps the bonus tile until someone else builds a LONGER road (i.e., 6 or more), which would reward the player who has not just the longest road, but the first-and-longest road. Is this correct? Or does the bonus go away when 2 or more players have the same length longest road?
A: If a player has the longest road, he retains the longest road card and it's two victory points until another player builds a road that is longer than his. So, player B would have to build a road of 6 segments in order to take the longest road card from player A. Of course, player A can make his road longer, so that player B would have to build even more segments before he takes it away.

The longest road card is retained by it's current owner until one of two things happen:


1. Another player builds a road that is then longer than the longest road of the current card-holder. In this case, the new longest road owner takes the longest road card.


2. The longest road is broken by the placement of a settlement along its length (remember to obey the 2-step rule). In this case, everyone must check to see who has the longest road. If any single player has the longest road (note that it could be the same as the old player with the longest road) than that player takes the card and the two points. If more than one player has the longest road, or if no player has a road of at least 5 segments, then no one gets the longest road card and it is set aside. As soon as any player builds a longest road of at least 5 segments, then he may claim the card as normal.