We often get some questions about 'disappearing' comments.
What happens is no big secret, but rather a sign that we are not relying on technology as much as people think we are. You see, we have a spam bot running in the background, constantly evaluating entries, weblogs, and comments, (and a few other things). While it catches most spam on the spot, sometime it goes into 'safe mode' and asks for the comment to be moderated rather than risking making a bad decision.
While this is happening, a notification is sent to you, informing you that there is a new comment on your blog. Been the super efficient bunch that we are, we often review comments very quickly and delete it if need be.
This means that, by the time you come to read your blog, you find nothing more than tumbleweeds.
Note that we don't judge any comments, we only remove spam comments, nothing more, nothing less any other form of comments will have to be moderated by yourself. You can go to your account and delete the comments you don't wish to see.
Also note that a copy of the comment is sent to you, if you feel that we were wrong, we will happily restore your comment...