I see that the "report" option is not available when you view only a single post (while the other accompanying icons are). That's very smart, since a comment could be taken out of context without reading the whole thread.
I also hope that the report icon will not keep a visible count, like the acorns and thumbs up do. This is not something to be taken lightly, and "getting on the bandwagon" is not something we should encourage with this feature, in my opinion. Reporting a post should be one's own decision, and not be encourage by others.