As a game that has promoted its PvP aspects so much, Warhammer Online's Realm vs Realm feature has become a big hit among players. In a recent article over at Eurogamer, they analyze the sport aspect of WAR's RvR system, and what makes it different from the PvP in other MMOs.
This article touches on many key points, including collision detection, control point logistics and more. However, this article is not simply another praise-fest. On the subject of what Mythic got right or wrong in RvR: "Right: always ensuring you've got something fast, satisfying and combat-centric to achieve, with none of the waiting around and grinding of... well, I won't bring up That Other Game here. Wrong: guarding capture points for a set number of seconds, or running a flag to specific spots to score points is so inescapably gamey, so artificial."