@msh210 @YEZ a change was made a few months back: normally a tag used on only one question is auto-deleted after a while (6 months, I think), but if it has a tag wiki it's now supposed to stay. So, when creating a new tag, or just when noticing low-usage ones, try to see if you can help with the wiki too.
Grumble. If whoever's comment flag I just declined is wondering why the decline when I deleted the comment... because I fat-fingered the interface, that's why. Oops.
@YEZ comments are already second-class (maybe third-class) citizens on Stack Exchange, and comment flags don't get much love (you can't even see which comments you flagged in your flag history, just that you flagged something), so I doubt this will change. (That said, I was sure I was clicking on "delete" not "dismiss", but the comment was still there when I refreshed the page later. Hmm.)
Anyway, if I've cost somebody 1/500th of a Marshal badge I'll offer 1/500th of an apology. :-) Fortunately, negative flags (within reason) don't do any harm.