londrum - 1:54 pm on Jul 18, 2012 (gmt 0)
a lot of blogs are set up to moderate the first post that someone makes, but after one has been accepted as legit the rest will be let through automatically.
i would guess that its something to do with that. they are submitting a load of normal looking stuff, that will more than likely be waved through without a thought, so they can post their proper spam stuff later.
its highly unlikely that a human is doing it. its more likely a bot. you need to install a captcha, or something like that, to block them