It's a shame that one or two people have to ruin it for the rest of us. Anyway, I have noticed that over the last few months some anonymous users were posting links in the comment sections. Sorry this is not an advertisement blog. That is not what the comment section is for and, well they know it.
As a result I am restricting the comment section to registered users only. I hope that will fix the problem. If not, well I will deal with that later.