WAR is awesome at PVP. PVE is the same in all MMOs, although WAR has a few twists to make them more interesting such as public quests.
WAR is very social, open groups allow players to jump into a group when your friends aren't on and make new friends easily! Realm vs Realm battles unifies players into factions and makes players help each other out much more.
For example, last night we had a running battle with about 50–75 on each side fighting for 4 battle objectives and 2 keeps. Siege weapons blasting away, NPC's pitching in to help, people healing and aiding allies, tactical retreats… nothing NOTHING in any other MMO comes near to this.