IGN got an Article about the Mage Talent Tree.  Read the three-pages article:

“Nine talent points have been freed up, thanks to several talents being changed from five increments to three or four. Arcane Explosion is now instant cast, and the talent that used to reduce its casting time now adds a critical hit boost. Evocation will be buyable from a trainer. A couple abilities have been removed, but those extra nine talent points mean you can max out a few abilities that were previously inaccessible. It may be advisable at this point to let warriors purchase Tactical Mastery at a trainer.”