[/quote] Personally i have yet to play a game that i feel has done PvP "right" yet within the genre. Balance issues aside, there are many different mechanics from many different games that simply do not cross over, but if combined would create the beginings of an environment for pvp that would start to qualify as "amazing". Moving away from the basics, such as defined roles, teams, team play, and goal orientated combat there are several "core mechanics" i have observed that really deserve to be pushed forward more. The Age of Conan combo system and positional style combat, which also includes the generic defensive manuvers and "shield system" isn't perfected yet, but a brilliant concept building on the generic auto attack based dogma that rules the genre. The positional style and movement based evasion on ranged combat within guildwars, combined with ground targetable options found in other games would also be a major improvement. Taking those two basic elements and combining it with Wii style sword control combat or Oblivion esque control (which needs to be updated more and improved) would be the basis of a foundation for something that could realistically be labeled as "amazing pvp".[/quote]
The Battlegrounds that WoW have are awesome. I think it's fair to include them because you are fighting other players in consentual team vs. team play. Blizzard has essentially wedged FPS play into an MMORPG. It's fantastic. Capture the Flag, Map Control Point game type, and I forget the others. Also there's four distinct, maybe more, battlegrounds to play on. I think that is an excellent example of PvP done right.

