WAR, without PvE, is just a mess waiting to happen. Online games, especially MMORPGs, thrive on diversity. The more things there are to do in a game, the more players it attracts. Differences between play styles and players build communities. Community is not built through forcing players into groups. It's been said a thousand times: things get pretty boring when everyone is the same.
WAR needs PvE and it needs PvE players. However, it's not pure PvE players that will make WAR great. It is the PvE player that wants a little bit of RvR every now and then that will be WAR's key demographic. There will be plenty of full-time RvR players in WAR, but I am betting that there will be far more part-timers.
But what is the benefit of all these part-timers? Simple. Sheep. PvP combat is always better when it is wolves vs sheep. When there is only wolves, PvP becomes static. The fights start becoming far too routine with the same wolves endlessly gnawing at each other for a bit of epeen. The non-wolves, finding there is really nothing for them to do, leave. Then the wolves start complaining that there isn't anyone around to fight.
I don't want to categorize all part-time RvR players as sheep, but there will be plenty of them that are not as strong in RvR as others. This creates a great dynamic in the RvR/PvP fighting.
The sheep can form and fight together against smaller packs of wolves, but when the going gets rough they CAN go do something else other than complain and quit. The sheep also provide an interesting change of pace because most often they RvR/PvP only when they are having fun. It is immensely better to be playing against an opponent that is having fun, even if it is in a losing effort.
With the sheep mixing into the wolf pack, it offers a chance for stronger players to help them out. DAoC was great when an entire realm worked together to take keeps or relics. It was very important for the stronger guilds to work and coordinate with the weaker guilds and players to form a cohesive team. Stronger players HAD to help weaker players if they wanted to accomplish the end-game goals of DAoC's RvR.
And that was all possible, because the weaker players weren't forced into RvR/PvP against their will. WAR has the same approach, but is setting the stage for the "sheep" to get more involved in RvR. This is good for WAR.