Just speculating, but heres a tri-spec i whipped up. mainly solo grinding/questing in mind. obviously not a great raid/pvp build but could work OK in either i guess - pvp has PoM/pyro combo for burst, some good raid talents in there too but there are better builds specific to each function obviously
http://www.wowhead.com/?talent=of0Ec0czZVxrz0cZbhGos0xo
The main idea of this build is to have a bit of AOE damage when its needed, but also has the added ability of killing a single target fast. Mana effitiency isn't the MOST important thing but is covered with a few talents
Frost tree is mainly for the Ice Block talent for defense and Shatter for crit boost to ALL spells.
improved Arcane Explosion for synergy with frost nova freeze and shatter - very high crit chance with Arcane Explosion and Shatter for super mana effitient DPS against 3+ enemies
PoM/ Pyroblast for burst damage, Scorch/Fireblast for fast recharging high crit chance single target DPS combined with the extra crit chance from shatter and the extras damage from ignitie this SHOULD serve good nuf single target DPS
Cone of Cold will be the primary "Chilling" spell to trigger the freeze proc, frost nova is obvious for proc. freeze for shatter
master of elements (combined with the extra crit chance talents), magic absorption and arcane concentration, arcane meditation serve to keep mana flowing at a pretty constant rate (4 mana effitiency talents BETTER keep the mana pool overflowing considering we have evocation also)