PvE:
-hunter needs huge dedication to get a decent dps and is mainly usefull for tranqshot, gameplay is a rotation between aimed shot, multi shot and auto-shot + pet management.
-warlock has a good dps but a very boring gameplay based on shadowbolt spam, only job beside that are banishings.
PvP:
- Hunter has a good dps, specially against clothies, with the longest range of the game, instant cc's and a huge mobility + powerfull manadrain.
- Warlock has either a huge dps (sm/ruin or destro) or a huge survivability (demono) + a pet that has independant abilities like an offensive/defensive dispell and a counterspell.
You have to choice between two gameplay, for me hunter is funnier but warlock is the real pvp endboss