There's a problem with world PVP - it's fun for the victors, and not for the ganked. Period.
I've played this game since Open Beta, just before it went live, and I've played since it went live. I remember world PVP. I remember the time some (f'n) horde guild was running MC (that meant there were 40 of them) and I wanted to run BRD. I remember it took me over 30 minutes of corpse dragging (rez away from your body towards your goal, get immediately ganked, run the long distance back, repeat) to get inside the instance.
World PVP can die in a fire. If MOP is as world-PVP centric as the smug dev mouthpieces make it sound, I won't be renewing my sub once the year's worth is over. I should never have started on a PVP realm, wouldn't have but I was following my idiot friends. I'm not about to pay to move all 7+ 85s I care about to a PVE realm either.
Also, I've played PVE - it's worse, in some ways - people flag themselves for PVP then stand near you when you're trying to kill mobs, hoping you'll AOE 'em by mistake so that they can then gank you. Or people flag themselves and run around never ceasing their crowing about how badass they are for being flagged all the time.
Here: I've uploaded a video one of us took (Not me) of the time we sacked Tarren Mill. I didn't create the video or choose the song, which I may need to strip out later. Still, the song works. That rage? In the song? That's what I felt the entire time, at the horde, at the tarren mill guards, etc. We were so tired of being ganked - levelling through South Shore was a frigging joke, most of us skipped it after a while.
http://www.youtube.com/watch?v=pcacDbFeaJQ
So to recap, world pvp - glad it's dead, hope it stays dead, afraid it won't stay dead, planning on quitting before MOP ships if it turns out that we're forced into world PVP.