++ 1
It seems to me this does even more than that.  Most importantly, it goes a long way toward aleviating the effects of the apparent "personality voting" (going through and --'ing all the posts of one person), by at least causing theses votes to be rather obvious.  For instance,
Zaxo sat and watched 20 of his posts get downvoted in 10 minutes.  If he hadn't happenned to notice while it was happenning, he could have come by a day or two later and simply thought he had had that much less response.
But more generally, for a post which has, say, 0 votes, it allows one to know if there was no interest at all or if 91 people loved it and 91 people hated it.  That's a huge amount of information which is entirely unavailable now.
(Of course, I have to add, lest someone take issue, that 91++ and 91-- is an extreme and unlikely example and that 0 is more likely the result of nothing.)
 
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