It seems like all the item counters have serious problems when you delete items before they are published in a moderated forum.
What happens is that the counter subtracts 1 when the post is deleted. However, the post has never been added to the counter and the result is that the counter is incorrect. To reproduce the error, simply create an empty moderated forum, post an item and delete it before it's published. The result should be an item counter of -1.
Another issue is the counter for "My posts". When an item is posted in a moderated forum, the post is automatically added to the My Posts counter. If the post is deleted before it's published, the "my posts counter" is not updated. Lets say I have posted 2 previous items and post number 3. Then the moderator deletes the post before it has been published, but my posts counter still reports 3 posts - even if I only have 2...
Since these two counters have errors in opposite directions, it might be possible that the problems are related to each other. Ie, wrong counter update when an item is deleted before it's published!?
If anyone may fix this - I'll be very happy! :)