It's in relation with this thread:
https://bitcointalk.org/index.php?topic=5365850.0You can read my reply there, but the update is that it has been dealt with, and hopefully shouldn't be a problem anymore. Although, if you do find some posts left over then report them so we can clean up, as they came thick, and fast we probably missed a couple.
I don't know how to defend the forum effectively from this type of attack, spammers seem to have found a weak point, and now they are massively exploiting it.
Not really, all forums are suspect to this sort of spam. I think it was dealt with quite quickly, and efficiently. They had minimal exposure, and there are things in place to protect against this sort of thing, but until you know what your up against, you can't counteract it. So, these sort of spam attacks are always worse when they've just began.