Well, I don't know for sure their implications in PvP, but I can give you some of the brigand "key" spell lines.
Back-stab: Must be behind the target, fairly large upfront damage and a high dot
Thrusts: Fair amount of damage and decreses attack speed of target.
Flurry: Two fairly hard hitting attacks back to back. No status debuff, but if the first misses the second misses
Whack: Must be in stealth, fairly large damage and decreses str. This is probably the prime opening move of many brigands as STR will reduce DPS of target.
Blade: Interupts target with a moderate amount of damage. Must be to the side
Cheap Shot: Our only stun until like 30ish, used to be 6 second stun, now is only 2 or so though.
Gouge: Moderate damage and reduces Pary of target
Black Jack: This was our MAIN pvp "killer" spell. It inflicted VERY LARGE damage (read like close to 2k at max level) and stunned the target also. Now though, the damage has been lowered a bit and it now only prevents you from changing directions. For some classes that can be a big hinderence, but you can still cast if you are a spell-caster.
We also have 1 AE spell that has an interupt effect on it also. Along with Black Jack we also get a fairly high damage spell called Rake, it has to be used from behind and will deal a fairly large amount of damage. It also will decrease your mitigation vs heat and cold damage by a fair amount. None of our spells will deal heat or cold damage though... so unless there is a mage type with them, it is mainly just for damage.
There are also a few debuff only (no damage) spells that will decrease your agi (so you can't dodge us as much) and slow you.
Edit: You should also check the official forums for the class discussion forums. Chances are there will be info on the spells/abilities that each class use there.
Edited, Jun 23rd 2006 at 10:34am EDT by Tomec