I love to observe some of these. It is like two drivers, complaining of who is to be blamed for damages, when driver1 was over speedlimit and had to stop quickly and driver2 was overspeedlimit front of car glued to driver1's back. Both sides are at fault, yet **** gets throw at other side no matter what. Except the poor bike that got hit.
Problem is not Alliance or Horde. It is player attitude, inability to turn off PVP, situations where one person wants to get his revenge on other person, because other person accidentally casted Chain Lighting when first one was bit too close and got struck. Oh and lack of things to do for level 60 characters, I guess PVP battlegrounds got boring since it wasn't fixed as PVE was, so they are looking for a replacement.
Lets not forget people that hate PVP in general and thus pick fights they know for sure they can win to get back at the dirty [insert enemy faction name here].
Oh and let us not forget whole quest item and resource war, where you are better off going level 45 to STV so it would be easier to obtain quest items and such.
Also people who have low ego. Those are a problem, but near impossible to fix. Unless you make server PVE... yet then they might find a way to annoy lower level player by stealing their mobs or something.