I hate the idea of intelligence increasing spell power so I hope they don't do that
Why? Isn't it logical the wiser one get's, the more powerfull? If not, spells get useless if mobs get stronger and their resistance get higher. Would it not be logic that if you are smarter, your more capable to master/finetune a spell?
See it as math. The basic is easy 1+1=2 evreybody can doe that, but if it get a bit more complicated? 16x8=128 When not so intelligent you might manage to give the answer, but slow=weak. While when you are like smart and stuf, you can answer instantly=strong.
It would be the same as not increasing vitality when raising constitution. Well, atleast that is my opinion. But I am not infallible. :p