Being on a pvp server, this is my area of expertise. Many times I will be out farming, grinding, questing, etc. and some how get what I call, "Rogue Aggro". It can happen at anytime, it can happen anywhere, even if you constantly keep "Track Humanoids" on you will never see the good rogues coming.
So to counter this, I've devised a few methods for when I'm out in the world, that are time consuming, but have saved me many a time. Maybe some of these tips will help you with world pvp, maybe not, up to you.
First let's take a look at our methods of actually detecting a rogue.
1) Flare - By far our best method of spotting a rogue stealthing near us. The smart one's always stay away, but sooner or later they to will be seen.
2) Freezing Trap - Rogues can see your traps, there's no doubt about that, the problem is they don't realize the range of your traps before it's to late.
3) Track Hidden - Usually not as useful but it can still help for when you're trying to track one down that's constantly been in hiding around you.
4) Speakers - Yea it sounds wierd doesn't it? Nothing is more helpful then a pair of these baby's, once you hear that rogue sound, you're paranoid for life.
So puting this into perspective, when I go grinding, questing, etc. I pick a spot that's some what a remote location, not a lot of mobs spawn near it, and I can tend to pull back to it in case I need to. This is my marker so to speak and I will always go back here in case something bad goes wrong.
That being said, I always have a Freezing Trap up in this one spot. If I get to many mobs at once, or manage to aggro something next to me I just fall back to my trap. The same can be said for a rogue that's trying to sneak up behind me. As soon as I get out of stunlock, I run back to the trap. The key here is always keeping that trap up.
I usually only flare after the rogue is frozen, and I place it directly on top of him, since they love to Vanish and get rid of your hunter's mark. Obviously the key here is distance. You want to keep your distance, and a rogue loves to sprint and constantly beat down on you while trying to proc their poisons to keep you from running away.
Fortunately I'm a Marksman Spec. I have Scatter Shot at my disposal but I only use it when absolutely necessary. If the rogue is not using poisons and I don't get snared, I'll wing clip them and run away to safety, so I can continue to pelt them. If they are using poisons, I will scatter shot only when I get snared, mark them again, and get an Aimed Shot out if there's enough time.
After that I use Jump-Shot with a mix of Concussion Shot + Arcane Shot to wittle down the Rogue before they run away or die. Whenever my trap's are up from cooldown I ALWAYS place a new one down, even if I don't intend for the rogue to get trapped by it just yet, I always have one down.
Now my main strategy does not involve Serpent Sting, mostly because I will not use dot's against a rogue unless I'm in a group or with at least 1 other person. The reason for this is because even though a Dot will reveal them after they stealth, it will negate your traps and get you killed just as easily. 15 second duration on a Dot can mean life and death because you couldn't trap the rogue for more then 2 seconds.
Now your pet plays a minor roll when you get jumped in the wild. 70% or more of the time I am jumped by a rogue, it is while I'm fighting something. Apparently when a rogue see's my pet engaged in a mob, and I'm firing, it's just a sign that says, "Gank Me!" You don't want to pull your pet back right away, because then the mob will come back with you, and possibly get caught in your trap that you're trying to save for the rogue.
If at all possible, trap the rogue, and then finish the mob. If the mob has to much life, keep the rogue trapped and go to town while your pet keeps the mob busy, after a while sic your pet on the rogue for added DPS and annoyance. The mob may eventually turn to you, which is what FD is for.
Always be mindful of your surroundings, you don't want to be running into that nest of furbolgs because you took a wrong turn some where. Become familiar with the area, know where you can and can't run for easy escapes if you need to.
Also, and this is very important, TRACK!! Use track for what you need it for, then switch. If I'm looking for beasts, I'll Track Beasts, find one I'm looking for, then switch immediately back to Track Humanoid or Track Hidden (yes I'm paranoid but it's saved me so many times).
Being a hunter we really only have to sit there while our pet tanks a mob. Sure you can throw in a shot or a sting here and there, but in all honesty you're really just sitting there with Auto-Shot on, use this time to scan your mini-map. Watch for things that are constantly moving, names of people in particular. Track Beasts also works well for druids, but for most of the druids that jump me they are usually in cat form anyway, and stealthed, so Track Hidden works just the same.
It takes extra time and effort to set this up, but in the end it becomes second nature and you'll find yourself doing it from habbit, even during instances, it just becomes an instinct that you need your trap up at any given moment.
I got strategies for all the different classes, but as you can see my explanations are elaborate, perhaps I should write a guide ;)