Taking a look at GvG, every single class had a few mechs in it, druids, mages, paladins, ect. The new mechanic being introduced in WotOG is C'Thun mechanics (and I've read that C'Thun is guaranteed in the free 3 WotOG packs you will get during the WotOG promo). I would say there is a 100% chance 1 neutral minion will be buffed by a buffed C'Thun, 95% chance that we will have 2, 80% chance we will have 3, and good chance (50-70%) that one of those 3 will be powerful enough that you have to save removal for it.
As for the class cards? If you do not think that every single class will get 1 card that has decent stats and gets buffed by C'Thun? You really should quit posting, period, and go see a psychiatrist, because there is something wrong with the way you think.