If anything, it should give an error. $null isn't really any more accurate than 0. It's just easier to deal with. Of course, in the majority of calculations, you know if it's divided by 0. Yes, if you're making a !calc script or something similar, you might not know. But most of the time, you do know what the numbers are and can easily check if it's divided by 0.
If we're going to change it, then we should do it the right way... throw a #DIV/0 error.
Anyhow, no matter how it's handled, the script will be required to deal with invalid math. And 0/0 is never equal to 1.
