Agree with this.
And I honestly don't believe Blizzard would lose any money by permabanning botters, they could even just do it like this: 3days ban first, with a note saying -" you will now be watched, and if we catch you again you'll get perma-banned."
I bet that would keep alot of people away from botting.
But then again, there is this problem with those that actuallt get hacked and those that play "mindless" (My GM actually thought I was botting, because when he spoke to me in /g I never replied. When all I was doing was slacking in BGs and watching movies.. :P)
The problem with hacked accounts should be easly figured out - Just check what IP adress the game was played on last, and then compare it to the other IP adresses used by this account, I'm sure that's possible? Gmail is doing it atleast.
The "mindless playing" problem on the other hand is more severe, maybe add a BLING sound when a GM wispers you (A sound that pops up even if you got sound disabled)