Maybe something like this would be better than up/down-votes.
(1) Replace the +/- with "flag as inappropriate"
(2) If you click "flag as inappropriate" the community guidelines are
displayed and you are asked to mark which ones have been broken.
(3) If you mark at least one and press submit, the comment will become hidden
by default but optionally displayable.
(4) "flag as inappropriate" is then replaced with "not inappropriate" or
something similar. If a certain number of people (2-3?) who aren't the author
of the comment click this, then the comment will be fully displayed again and
no-one can re-flag it.
