As a variant of this software, it could be perfect for voting and signing up to lists for users who aren't familiar with markup. I've previously done some experiments with using preload for signing up (template, in use), and for support/oppose (template, in use) but it's not exactly a smooth experience for newcomers.
Perhaps some magicword in the lead comment could alter the behaviour if its [reply] link, e.g.
__VOTE__could make the reply button replaced with a [vote on proposal] button that allows people to choose from support/oppose/comment
__SIGNUP__could be even simpler, just completely the comment box so that when someone saves, it just adds their signature