Mark as spam control is obtrusive

If you must repeat yourself in a UI, do it unobtrusively. Things that help:

- Brevity. In Ubuntu Software Center reviews we use a single word with a question mark -- "Inappropriate?" -- and we don't put an icon next to it. (Using an edit icon for marking spam makes no sense anyway.) Some Web sites go the opposite route, using just a flag icon with no text (see for example the Disqus theme currently used by OMG Ubuntu).

- Dimness. In USC we make the link light grey, and this is fairly common in other forums.

- Compactness. Put the link on the same row as other metadata. Launchpad bug comments are awfully laid out generally (a hangover from the Plone era that I never got around to fixing), but at the very least the link could be on the same row as the commenter and date.

Making the link light grey contradicts the rule that links that change the page content are green. I favour only showing the link when my pointer of over the comment, or when something in the comment has focus.

+1 re moving to the bar with the other metadata.

I'm not sure about text like "Inappropriate?" That doesn't tell me I'm about to take real action, as opposed to just flagging something for someone to look at.

Since this is an admin-only interface I think just having an icon
(with title/tooltip text) would be totally sufficient, perhaps just
the "x" icon. Separately we can add a "flag for review" that users
can push.

Yes, the "Inappropriate?" link in USC is for non-admins to flag a comment for review. Admins have a separate aggregated review interface.