All part of the eternal cat and mouse cycle between Blizzard and botters. It doesn't seem to me like Blizzard has (or intends on developing) any sort of automated system to reliably catch bots. It's like they wait until a critical mass is reached, then ban every one of them at once. There might be some monetary reason for this; i.e. give the botters hope that subbing and botting is worthwhile.
Originally Posted by Drakanian
Either way, bots don't bother me that much so long as my Shaldorei Silk market is untouched. This is also why I don't stock herbs in large quantities...