My '69' render is now on page 67, so a few posts have indeed disappeared/been deleted or self-deleted since I posted that render. As to the 'why', we may never know...
A few posts disappeared from the DMD art thread recently as well, I did notice when the post count dropped by 3 suddenly a couple of weeks back.
A while back a number of renders that I particularly liked from a specific member were scrubbed from the 'Show Us Your Daz Skill' thread, no idea on the whom or why, but the point is that stuff happens occasionally and no sense worrying about it, life is too short.