my theory of bans is:
* excessive games per hour - more than 4 gets a ban
* excessive client ids from the same hardware id - d3 sends unique hardware id to blizz, if too many clients are logged for too long on the same hardware means ban - VMWare does protect from this
* excessive errors from a client (game creating)
* enormous game time like 10k hours
* joing public games with a bot - people will report you
* using a program for disabling rendering device (to speed up graphics)
* using strange plugins (I dont think gearswap is safe)
So any 1 of these conditions can get u a ban. In my case I was protected only from the first 2 ones, all other not.
They also manually somehow check each case after finding out these behaviours.
Anyway all bans are Tuesday night or Saturday night, wonder what will happen tomorrow.
I have botted since the release of vanilla d3 and read most ban reports since. And btw. I was running 33 accounts all banned last Sat, this is what was left from gold farming days and RMAH.