By far, the most common Cabalist spec used. It grants the most utility a Cabalist can possibly have that is even effective at low RealmRank. 25 Matter Destruction grants blue tier (45%) Nearsight, just enough to silence most enemy spell-users. 33 Spirit Magic grants the yellow tier Body Resist (30%) Debuff, this is where most of your damage comes in - debuffing your own damage type, in conjunction of a Sorcerer or another Cabalist assisting for damage. The 34 Body Magic grants the yellow tier AoE Disease, thus should lead to less resists, and narrows the variance of your Baseline Body Lifetap (Improves your Damage).
I know some other Cabalists run 32 Matter Magic for the yellow tier (55%) Nearsight, dropping their Body Magic to 28. I'd only see this viable if you were a high RealmRank Cabalist. Even then, I personally would stick to the above 25/33/34 spec, I just don't see the extra 10% to Nearsight to be worth losing some damage.
RA:
Requirements on a Cabalist: - Long Wind I - Purge I - Serenity I + - Augmented Dexterity II + - Physical Defense II + - Mastery of Focus II + - Raging Power I
Once you get those basics, then you can build up on grabbing higher tiers of those basics and throw in some Wild Power.
"Juggernaut" in combination of Cabalist rr5. It's just not worth it for an RvR Spec unless you're high RR and can afford to dump extra points. A well-played group will recognize Cabalist rr5 and will either kill the Pet or kill the Cabalist itself as soon as possible.
"Mystic Crystal Lore" - as I had a guildmate say very often. If he is able to use this, he can Pet Recycle. Since most of the time you and/or the Pet have a target, very rarely will you have a chance to utilize this RA. The main issue, is when you're focusing someone down and need an instant replenishment mid-nuke - that's where Raging Power comes in.
"Mastery of Focus" - it's all preference here as to how much you invest here. I suggest obtaining at least the level II tier. I always found myself spamming AoE Disease on Trains anyway since there is always someone resisting. In the end, it doesn't matter how much you invest into MoF as a caster, you'll still get screwed over by the lousy 13%ish flat resist rate.