Wow. Things just got real. Those are some absolutely massive changes. People have been debating if and/or how to nerf the Wizard for awhile, so it's nice to see Arcane Wonders finally weighing in. These aren't even close to the changes I personally would have made, but I'm absolutely sure the staff have playtested these ideas VERY carefully, so I'm excited to see how it goes.
In hindsight, the change to an air-only Wizard was strongly hinted at based on the similar nature of the Academy Wizard. I'm still not sure what I think about this change. It definitely limits his card pool availablity (which had contributed to keeping him a top-tier pick throughout Mage Wars' entire existence). On the other hand, the Wizard's ability to choose a limited specialization is what most set him apart from other mages, and I'm a bit sad to see that ability disappear entirely. Plus, there's no real thematic reason for a Wizard to be associated with air over any other element. Presumably air was picked because every other element already has an associated mage (earth has Warlord, fire has Warlock, and soon water will have Siren).
I'm surprised the developers didn't go the obvious and simple route of making the Wizard's Tower epic, but I kind of like what they did with it. The Wizard in the core set (before he starting mutating by "stealing" other schools' cards and abusing the toolbox nature of the tower) was usually geared towards delaying his opponent's ideal actions so that the Wizard had a short-term advantage until he either won the fight or ran out of tricks. The new Wizard's Tower looks like it will help with that playstyle. It provides potential extra firepower and board control every turn, but at the cost of burning through the Wizard's stockpile of attack spells. Now the Wizard actually has to choose between conservation (an Elemental Wand) and action efficiency (the Wizard's Tower).
Regardless of how things turn out eventually, these two changes pretty much force every existing Wizard player to radically alter his/her spellbook (since most of them are now illegal). The next Gen Con tournament is going to be very interesting.