Just how does one figure out his chance to get a critical hit when casting a spell? It'd be handy to know how much of a contribution Intellect makes, when weighing a change in gear.

I wish there was a spellcasting icon in the General Skills tab, like the attack icon. But until Blizzard adds that bit of information, we're stuck doing the math on our own.

General consensus seems to be that 100 Intellect = 1% chance to crit.

With a base of what? 5%?

With an undetermined base. Some tests seem to imply a base of 0% - that's right, no base crit at all. The possible issue with Eye of the Beast, where it provides -2% to spell crit instead of +2% to spell crit, might have to do with it. More testing is needed on this issue.

I was reading up on this at Blizzard's mage forum yesterday. Another number that a few people were concluding with was 3.5%. Of course, the "100 int = 1%" thing might just be at level 60, when a lot of the testing is done. The formula might be different at lower levels.

I don't know. It's all very confusing. However, a Blizzard representative has said that in the future they intend to have the UI designate chance for spells to crit. How exactly this will be displayed is anyone's guess, since crit chances can vary on a per-spell basis.

Wierd. I had always heard 30 int = 1% spell crit rate with a base of 1%, but I have no hard evidence to back it up.