Got any drawing examples to filter out which is which?
Ah, well... It's not too hard to figure out who are the spam bots.
Usually speaking, the spam bots will have a few posts with very short messages in 5 different threads. Said posts will often times be completely unrelated to the thread, or just tangentially related without really saying anything.
Then, they'll have one longer post that talks about X thing that is great and will link to a website where you can test X thing yourself (or buy it).
That's basically the gist of what most spam bots do... Generally speaking, if you see a fairly new account with a post that is advertising a 3rd party site, then it's probably a bot.
Similarly, if you see a fairly new account suddenly bumping a bunch of old threads to make very short comments, it's probably a bot too.