The captcha we have seems like first-generation or something. I'm pretty sure it isn't a hurdle for bots. Well... obviously it's not.
Really, the only approach we have currently is IP banning, and we're sorting out the ranges they're coming from, but there are A LOT. And it's an all-day affair, every day, 24/7. So eventually, when all of China is IP banned, then we'll have some peace.
