I don't know if it's too early to call this a problem, but two usernames with seemingly identical style, notation and subject matter have spammed a total of 10 questions today. (Not that asking a lot of questions is wrong, it's just that they all show no effort, and the user seems unresponsive and bot-like.)
They seem to be rapid fire, and being posted without any effort to determine if there is a duplicate. I haven't fully absorbed from the meta posts when exactly this qualifies as a problem. At worst, it is a person posting an entire homework assignment, but of course we have little ability to prove that.
When should a concerned forum user do something, and what should they do?