at level 80 there are lots of different ways to set your talents for max DPS. if you have good mana regeneration and set the right talents, arcane will probably be the best spec (specification).
there are several ways to set your talents within the arcane talent tree.
the most required talents are:
-arcane focus 3/3 -arcane stability 5/5 -magic absorption 2/2 -arcane concentration 5/5 -magic attunement 2/2 -spell impact 3/3 -student of the mind 3/3 -focus magic 1/1 (important for all DPS specs) -arcane shielding 2/2 -torment of the weak 3/3 (important for all DPS specs) -presence of mind 1/1 -arcane mind 5/5 -arcane instability 3/3 -arcane potency 2/2 -