Thinking about this issue (delete feature):
Paul Jenkins sums it up on Twitter:
@mabster except that they're still indexed by google/publically accessible if you guess the url, which can be annoying
I'm wary of implementing a "hard delete" feature though, because if you want to bring the page back to life at some point, it's gone.
What might be better is to mark a page as being "private". When you do that, only logged in users can see the page - for everyone else it 404's. So in effect it's a delete, but you can always unhide it later.
It would also be useful to hide any pages as you're composing them, then unhide them when you publish.
What do you think?
Paul