TBH you can do a lot in WoW while leveling too.
Things is, there are a couple more things you can do at 70....and most are also more fun.
I dont see how this would be different in WAR, the higher you get the more you can do and the more fun it gets.
More fun because of more skills, better equipment, better grasp of you class etc.
After a game has matured and been around for a while, there is also a lot more people at max level which makes a big difference.
When i tried War i was basically doing exactly the same as WoW. Scenarios/BGs and Quests and PQ/Instances. When i went to a Keep i was greeted with crickets chirping in the distance. So all in all you pretty much do the same things when leveling up.
Perhaps WoW has more to do in endgame. Because you get raids and Arena, whereas War only gets City Sieges AFAIK.