Well, the editor does not really know a new site has been suggested, he only knows how many sites have been suggested. So unless the editor happens to remember what the count was yesterday, it's not going to be obvious that a new suggestion just arrived. On the other hand, it's not really that important to most editors that anything is new.
In some areas I actually remember pretty much remember what the counts are, and will notice new stuff, so I will go and look at it, to make sure it's waiting it the right category, a large percentage are grosslly misplaced or are spam and get either deleted or moved to another editor.
For an editor who only has a couple of categories, so his potential work load is very low, and likes to stay on top of things and had no sites waiting to be reviewed, it will be very obvious that something has just been added.
Since there is no email notification of any of this, all of this depends on the editor logging in and looking at the counts.