Apologies if any comments may have been taken for spam and deleted recently. The site is being attacked by hundreds, if not thousands, of spam comments a day, mostly originating from one server in Panama. I do not have time to go through everything in the spam queue, so I have just had to delete everything. If any comments go missing, just post a simple comment letting me know it has been lost and I will then recover it from the spam / moderation queue.
In general, though, try to avoid having more than one link in any comment as this will usually mean that it is not identified as spam.