NGD logs game statistics automatically per server, and some of them are displayed in public view as what is called "Rankings". They get updated daily and cover a wide range of statistics.
Player Rankings[]
Naturally, statistics on a character basis are logged and ranked. Both PvP and PvE performance of a character is ranked.
Heroes (PvP Rankings)[]
Since the game's focus is on PvP in the form of RvR, these rankings represent the most important aspect of a character's in-game performance.
Top Player[]
Currently in beta, this ranking is a weekly ranking that collects statistics from Monday to Sunday, and the results are renewed on the site every Monday. It is a Top 30 ranking of the highest "Personal Score" players in the server for the previous week. "Personal Score" is a composite metric used by NGD and it takes into account the general RvR war performance of a character, such as participation in Invasions, fort battles, kill/death ratio, etc. The exact formula is not available to the public, and the feature is still in beta. The #1 player in these rankings gets a special mention in the rankings home page, and NGD has stated that once the feature is out of beta, in-game rewards will also be awarded to each week's #1 Top Player.
Champions[]
This ranking keeps track of RP gained by players. It is a persistent ranking, this means that there is no reset. It displays the Top 30 players in RP score globally, or per realm, class, or race.
Gladiators[]
This ranking is supposed to keep track of kills in the arena for each player, however it has never functioned. Apparently it is also a persistent Top 30 ranking that displays either global, per realm, class, or race rankings.
Legends (PvE Rankings)[]
PvE rankings are of secondary importance due to the PvP focus of the game, however some players strive for these rankings as well.
Experience[]
A persistent Top 30 ranking based on the Experience gathered by characters. It displays the Top 30 players in XP score globally, or per realm, class, or race.
Wealth[]
A persistent Top 30 ranking based on the Gold gathered by characters. It displays the Top 30 players in Gold globally, or per realm, class, or race.
Quests[]
A persistent Top 30 ranking based on quests completed by characters. It displays the Top 30 players by quests completed per realm, race and class only (no global ranking).
Clan Rankings[]
Statistics for clans are also displayed to provide some sort of comparison between the performance of the different clans in the game.
Heroic[]
This is a persistent Top 30 ranking based on the total RP gathered by the clan members. It displays the Top 30 clans in total RP score globally or per realm. It also displays the total members of each ranked clan.
Legendary[]
This is a persistent Top 30 ranking based on the total XP gathered by the clan members. It displays the Top 30 clans in total XP score globally or per realm. It also displays the total members of each ranked clan.
Wealthy[]
This is a persistent Top 30 ranking based on the total GP gathered by the clan members. It displays the Top 30 clans in total GP score globally or per realm. It also displays the total members of each ranked clan.
Realm Rankings[]
This ranking displays the total amount of "Enemy Casualties" (kills) inflicted by a realm, as well as "Own Casualties" (deaths). It also displays a "War Performance" ratio (kills/deaths). These are presented comparatively for each realm, and there are 2 comparison tables: One for the previous day, and one for the last 30 days.
The rankings can be found here