I think it's been said that this sort of thing isn't going to be put into core MyBB and even if it was it wouldn't be until 2.0 which is a fair way off.
(2010-03-05, 11:21 PM)MattRogowski Wrote: [ -> ]It's in the current version, called unapproving...
He is not really talking about soft delete, he is also asking about the first part which basically shows a place holder where the thread or post was when its deleted or unproved to let people know there was something there. They do that on this forum:
http://forums.whirlpool.net.au/