Its perks are 2 fold. Intel not so much for spell power and crit (although both are nice side effects), but more for the increased mana, which leads to more arcane blasts, higher mana returned from evocate and the like.
its real benefit is from the on use ability, as it can be lined up with all your cooldowns creating a much more powerful burst phase that is guarenteed.
i was actually wandering the same..if talisman of resurgence is worth taking for arcane..have to upgrade my head and make that merlin robe (stupid northrend beasts hc robe aint dropping) so i dont want to waste 50 badges for nothing. plz give some more info about it