There is no way to know for sure. The reports here include serious gold-farmers, whom *I guess* are treated differently.
If this makes you feel any better. I have 1 BNET account with 6 WoW accounts (Max is 8, so 2 more for later)
Out of 6 WoW accounts, 2 have been banned, temporarily. It says "Suspension"
I don't bot for profit. I keep around 100k in the bank should I need it and try to farm when I can.
From what I understand, so long as it's not a manual ban where a GM is investigating your account, you should be OK.
Typically, you see BNET bans saved for gold-sellers. I don't waste a second thought on VPN, new BNET's, ect. When I get banned, I just create or re-activate the next account.
I know I'll get hit with a "detection" ban eventually, but Blizz hasn't given me a reason to think that my primary WoW1 on my BNET is in danger. Until then I'll be farming mounts, transmogs, heirlooms, pets, as well as creating lvl 110's to play after I wait out the first suspension of 6month.
"Quickest" way to get banned is farm gold all day, and sell the shit out of it for real money.